Isidor Isaac Rabi

Isidor Isaac Rabi (/ˈrɑːbi/; born Israel Isaac Rabi, 29 July 1898 – 11 January 1988) was an American physicist who won the Nobel Prize in Physics in 1944 for his discovery of nuclear magnetic resonance, which is used in magnetic resonance imaging. He was also one of the first scientists in the United States to work on the cavity magnetron, which is used in microwave radar and microwave ovens.

Born into a traditional Jewish family in Rymanów, Galicia, in what was then part of Austria-Hungary, Rabi came to the United States as a baby and was raised in New York's Lower East Side. He entered Cornell University as an electrical engineering student in 1916, but soon switched to chemistry. Later, he became interested in physics. He continued his studies at Columbia University, where he was awarded his doctorate for a thesis on the magnetic susceptibility of certain crystals. In 1927, he headed for Europe, where he met and worked with many of the finest physicists of the time.

In 1929, Rabi returned to the United States, where Columbia offered him a faculty position. In collaboration with Gregory Breit, he developed the Breit–Rabi equation and predicted that the Stern–Gerlach experiment could be modified to confirm the properties of the atomic nucleus. His techniques for using nuclear magnetic resonance to discern the magnetic moment and nuclear spin of atoms earned him the Nobel Prize in Physics in 1944. Nuclear magnetic resonance became an important tool for nuclear physics and chemistry, and the subsequent development of magnetic resonance imaging from it has also made it important to the field of medicine.

During World War II he worked on radar at the Massachusetts Institute of Technology (MIT) Radiation Laboratory (RadLab) and on the Manhattan Project. After the war, he served on the General Advisory Committee (GAC) of the Atomic Energy Commission, and was chairman from 1952 to 1956. He also served on the Science Advisory Committees (SACs) of the Office of Defense Mobilization and the Army's Ballistic Research Laboratory, and was Science Advisor to President Dwight D. Eisenhower. He was involved with the establishment of the Brookhaven National Laboratory in 1946, and later, as United States delegate to UNESCO, with the creation of CERN in 1952. When Columbia created the rank of University Professor in 1964, Rabi was the first to receive that position. A special chair was named after him in 1985. He retired from teaching in 1967 but remained active in the department and held the title of University Professor Emeritus and Special Lecturer until his death.

Isidor Isaac Rabi
Head and shoulders of man in suit and tie wearing glasses
Rabi, photographed in 1944
Born
Israel Isaac Rabi

29 July 1898
Died11 January 1988 (aged 89)
CitizenshipUnited States
Alma materCornell University
Columbia University
Known forNuclear magnetic resonance
Rabi cycle
Rabi problem
Awards
Scientific career
FieldsPhysics
InstitutionsColumbia University
MIT
ThesisOn the principal magnetic susceptibilities of crystals (1927)
Doctoral advisorAlbert Potter Wills
Doctoral students
Signature
I. I. Rabi signature

Early years

Israel Isaac Rabi was born on 29 July 1898 into a Polish-Jewish Orthodox family in Rymanów, Galicia, in what was then part of Austria-Hungary but is now Poland. Soon after he was born, his father, David Rabi, emigrated to the United States. The younger Rabi and his mother, Sheindel, joined David there a few months later, and the family moved into a two-room apartment on the Lower East Side of Manhattan. At home the family spoke Yiddish. When Rabi was enrolled in school, Sheindel said his name was Izzy, and a school official, thinking it was short for Isidor, put that down as his name. Henceforth, that became his official name. Later, in response to anti-Semitism, he started writing his name as Isidor Isaac Rabi, and was known professionally as I.I. Rabi. To most of his friends and family, including his sister Gertrude, who was born in 1903, he was known simply as "Rabi", which was pronounced "Robby". In 1907, the family moved to Brownsville, Brooklyn, where they ran a grocery store.[1]

As a boy, Rabi was interested in science. He read science books borrowed from the public library and built his own radio set. His first scientific paper, on the design of a radio condenser, was published in Modern Electrics when he was in elementary school.[2][3] After reading about Copernican heliocentrism, he became an atheist. "It's all very simple", he told his parents, adding, "Who needs God?"[4] As a compromise with his parents, for his Bar Mitzvah, which was held at home, he gave a speech in Yiddish about how an electric light works. He attended the Manual Training High School in Brooklyn, from which he graduated in 1916.[5] Later that year, he entered Cornell University as an electrical engineering student, but soon switched to chemistry. After the American entry into World War I in 1917, he joined the Student Army Training Corps at Cornell. For his senior thesis, he investigated the oxidation states of manganese. He was awarded his Bachelor of Science degree in June 1919, but since at the time Jews were largely excluded from employment in the chemical industry and academia, he did not receive any job offers. He worked briefly at the Lederle Laboratories, and then as a bookkeeper.[6]

Education

In 1922 Rabi returned to Cornell as a graduate chemistry student, and began studying physics. In 1923 he met, and began courting, Helen Newmark, a summer-semester student at Hunter College. In order to be near her when she returned home, Rabi continued his studies at Columbia University, where his supervisor was Albert Wills. In June 1924 Rabi landed a job as a part-time tutor at the City College of New York. Wills, whose specialty was magnetism, suggested that Rabi write his doctoral thesis on the magnetic susceptibility of sodium vapor. The topic did not appeal to Rabi, but after William Lawrence Bragg gave a seminar at Columbia about the electric susceptibility of certain crystals called Tutton's salts, Rabi decided to research their magnetic susceptibility, and Wills agreed to be his supervisor.[7]

Measuring the magnetic resonance of crystals first involved growing the crystals, a simple procedure often done by elementary school students. The crystals then had to be prepared by skillfully cutting them into sections with facets that had an orientation different from the internal structure of the crystal, and the response to a magnetic field had to be painstakingly measured. While his crystals were growing, Rabi read James Clerk Maxwell's 1873 A Treatise on Electricity and Magnetism, which inspired an easier method. He lowered a crystal on a glass fiber attached to a torsion balance into a solution whose magnetic susceptibility could be varied between two magnetic poles. When it matched that of the crystal, the magnet could be turned on and off without disturbing the crystal. The new method not only required much less work, it also produced a more accurate result. Rabi sent his thesis, entitled On the Principal Magnetic Susceptibilities of Crystals, to Physical Review on 16 July 1926. He married Helen the next day. The paper attracted little fanfare in academic circles, although it was read by Kariamanickam Srinivasa Krishnan, who used the method in his own investigations of crystals. Rabi concluded that he needed to promote his work as well as publish it.[8][9]

Like many other young physicists, Rabi was closely following momentous events in Europe. He was astounded by the Stern–Gerlach experiment, which convinced him of the validity of quantum mechanics. With Ralph Kronig, Francis Bitter, Mark Zemansky and others, he set out to extend the Schrödinger equation to symmetric top molecules and find the energy states of such a mechanical system. The problem was that none of them could solve the resulting equation, a second-order partial differential equation. Rabi found the answer in a book by the 19th-century mathematician Carl Gustav Jacob Jacobi. The equation had the form of a hypergeometric equation to which Jacobi had found a solution. Kronig and Rabi wrote up their result and sent it to Physical Review, which published it in 1927.[10][11]

Europe

In May 1927, Rabi was appointed a Barnard Fellow. This came with a stipend of $1,500 ($21,635 in 2018 dollars[12]) for the period from September 1927 to June 1928. He immediately applied for a year's leave of absence from the City College of New York so he could study in Europe. When this was refused, he resigned. On reaching Zürich, where he hoped to work for Erwin Schrödinger, he met two fellow Americans, Julius Adams Stratton and Linus Pauling. They found that Schrödinger was leaving, as he had been appointed head of the Theoretical Institute at Friedrich Wilhelm University in Berlin. Rabi therefore decided to seek a position with Arnold Sommerfeld at the University of Munich instead. In Munich, he found two more Americans, Howard Percy Robertson and Edward Condon. Sommerfeld accepted Rabi as a postdoctoral student. German physicists Rudolf Peierls and Hans Bethe were also working with Sommerfeld at the time, but the three Americans became especially close.[13]

On Wills' advice, Rabi traveled to Leeds for the 97th annual meeting of the British Association for the Advancement of Science, where he heard Werner Heisenberg present a paper on quantum mechanics. Afterwards, Rabi moved to Copenhagen, where he volunteered to work for Niels Bohr. Bohr was on vacation, but Rabi went straight to work on calculating the magnetic susceptibility of molecular hydrogen. After Bohr returned in October, he arranged for Rabi and Yoshio Nishina to continue their work with Wolfgang Pauli at the University of Hamburg.[14]

Although he came to Hamburg to work with Pauli, Rabi found Otto Stern working there with two English-speaking postdoctoral fellows, Ronald Fraser and John Bradshaw Taylor. Rabi soon made friends with them, and became interested in their molecular beam experiments,[15] for which Stern would receive the Nobel Prize in Physics in 1943.[16] Their research involved non-uniform magnetic fields, which were difficult to manipulate and hard to measure accurately. Rabi came up with the idea of using a uniform field instead, with the molecular beam at a glancing angle, so the atoms would be deflected like light through a prism. This would be easier to use, and produce more accurate results. Encouraged by Stern, and greatly assisted by Taylor, Rabi managed to get his idea to work. On Stern's advice, Rabi wrote a letter about his results to Nature,[15] which published it in February 1929,[17] followed by a paper entitled Zur Methode der Ablenkung von Molekularstrahlen ("On the method of deflection of molecular beams") to Zeitschrift für Physik, where it was published in April.[18]

By this time the Barnard Fellowship had expired, and Rabi and Helen were living off a $182 per month stipend from the Rockefeller Foundation. They left Hamburg for Leipzig, where he hoped to work with Heisenberg. In Leipzig, he found Robert Oppenheimer, a fellow New Yorker. It would be the start of a long friendship. Heisenberg departed for a tour of the United States in March 1929, so Rabi and Oppenheimer decided to go to the ETH Zurich, where Pauli was now the professor of physics. Rabi's education in physics was enriched by the leaders in the field he met there, which included Paul Dirac, Walter Heitler, Fritz London, Francis Wheeler Loomis, John von Neumann, John Slater, Leó Szilárd and Eugene Wigner.[19]

Molecular Beam Laboratory

On 26 March 1929, Rabi received an offer of a lectureship from Columbia, with an annual salary of $3,000. The dean of Columbia's physics department, George B. Pegram, was looking for a theoretical physicist to teach statistical mechanics and an advanced course in the new subject of quantum mechanics, and Heisenberg had recommended Rabi. Helen was now pregnant, so Rabi needed a regular job, and this job was in New York. He accepted, and returned to the United States in August on the SS President Roosevelt.[20] Rabi became the only Jewish faculty member at Columbia at the time.[21]

Atomic physicists Ernest O. Lawrence, Enrico Fermi, and Isidor Rabi - NARA - 558595
Rabi (right) with fellow Nobel Prize winners Ernest O. Lawrence (left) and Enrico Fermi (center)

As a teacher, Rabi was underwhelming. Leon Lederman recalled that after a lecture, students would head to the library to try to work out what Rabi had been talking about. Irving Kaplan rated Rabi and Harold Urey as "the worst teachers I ever had".[22] Norman Ramsey considered Rabi's lectures "pretty dreadful",[22] while William Nierenberg felt that he was "simply an awful lecturer".[23] Despite his shortcomings as a lecturer, his influence was great. He inspired many of his students to pursue careers in physics, and some became famous.[24]

Rabi's first daughter, Helen Elizabeth, was born in September 1929.[25] A second girl, Margaret Joella, followed in 1934.[26] Between his teaching duties and his family, he had little time for research, and published no papers in his first year at Columbia, but was nonetheless promoted to assistant professor at its conclusion.[25] He became a professor in 1937.[27]

In 1931 Rabi returned to particle beam experiments. In collaboration with Gregory Breit, he developed the Breit-Rabi equation, and predicted that the Stern–Gerlach experiment could be modified to confirm the properties of the atomic nucleus.[28] The next step was to do so. With the help of Victor W. Cohen,[29] Rabi built a molecular beam apparatus at Columbia. Their idea was to employ a weak magnetic field instead of a strong one, with which they hoped to detect the nuclear spin of sodium. When the experiment was conducted, four beamlets were found, from which they deduced a nuclear spin of ​32.[30]

Rabi's Molecular Beam Laboratory began to attract others, including Sidney Millman, a graduate student who studied lithium for his doctorate.[31][32] Another was Jerrold Zacharias who, believing that the sodium nucleus would be too difficult to understand, proposed studying the simplest of the elements, hydrogen. Its deuterium isotope had only recently been discovered at Columbia in 1931 by Urey, who received the 1934 Nobel Prize in Chemistry for this work. Urey was able to supply them with both heavy water and gaseous deuterium for their experiments. Despite its simplicity, Stern's group in Hamburg had observed that hydrogen did not behave as predicted.[33] Urey also helped in another way; he gave Rabi half his prize money to fund the Molecular Beam Laboratory.[34] Other scientists whose careers began at the Molecular Beam Laboratory included Norman Ramsey, Julian Schwinger, Jerome Kellogg and Polykarp Kusch.[35] All were men; Rabi did not believe that women could be physicists. He never had a woman as a doctoral or postdoctoral student, and generally opposed women as candidates for faculty positions.[36]

At the suggestion of C. J. Gorter, the team attempted to use an oscillating field.[37] This became the basis for the nuclear magnetic resonance method. In 1937, Rabi, Kusch, Millman and Zacharias used it to measure the magnetic moment of several lithium compounds with molecular beams, including lithium chloride, lithium fluoride and dilithium.[38] Applying the method to hydrogen, they found that the moment of a proton was 2.785±0.02 nuclear magnetons,[39] and not 1 as predicted by the then-current theory,[40][41] while that of a deuteron was 0.855±0.006 nuclear magnetons.[39] This provided more accurate measurements of what Stern's team had found, and Rabi's team had confirmed, in 1934.[42][43] Since a deuteron is composed of a proton and a neutron with aligned spins, the neutron's magnetic moment could be inferred by subtracting the proton's magnetic moment from the deuteron's. The resulting value was not zero, and had a sign opposite to that of the proton. Based on curious artifacts of these more accurate measurements, Rabi suggested that the deuteron had an electric quadrupole moment.[44][45] This discovery meant that the physical shape of the deuteron was not symmetric, which provided valuable insight into the nature of the nuclear force binding nucleons. For the creation of the molecular-beam magnetic-resonance detection method, Rabi was awarded the Nobel Prize in Physics in 1944.[46]

World War II

Original cavity magnetron, 1940 (9663811280)
Anode block of an original cavity magnetron, showing the resonant cavities, developed by John Randall and Harry Boot at Birmingham University

In September 1940, Rabi became a member of the Scientific Advisory Committee of the U.S. Army's Ballistic Research Laboratory.[47] That month, the British Tizard Mission brought a number of new technologies to the United States, including a cavity magnetron, a high-powered device that generates microwaves using the interaction of a stream of electrons with a magnetic field. This device, which promised to revolutionize radar, demolished any thoughts the Americans had entertained about their technological leadership. Alfred Lee Loomis of the National Defense Research Committee decided to establish a new laboratory at the Massachusetts Institute of Technology (MIT) to develop this radar technology. The name Radiation Laboratory was chosen as both unremarkable and a tribute to the Berkeley Radiation Laboratory. Loomis recruited Lee DuBridge to run it.[48]

Loomis and DuBridge recruited physicists for the new laboratory at an Applied Nuclear Physics conference at MIT in October 1940. Among those who volunteered was Rabi. His assignment was to study the magnetron, which was so secret that it had to be kept in a safe.[49] The Radiation Laboratory scientists set their sights on producing a microwave radar set by 6 January 1941, and having a prototype installed in a Douglas A-20 Havoc by March. This was done; the technological obstacles were gradually overcome, and a working US microwave radar set was produced. The magnetron was further developed on both sides of the Atlantic to permit a reduction in wavelength from 150 cm to 10 cm, and then to 3 cm. The laboratory went on to develop air-to-surface radar to detect submarines, the SCR-584 radar for fire control, and LORAN, a long-range radio navigation system.[50] At Rabi's instigation, a branch of the Radiation Laboratory was located at Columbia, with Rabi in charge.[51]

In 1942 Oppenheimer attempted to recruit Rabi and Robert Bacher to work at the Los Alamos Laboratory on a new secret project. They convinced Oppenheimer that his plan for a military laboratory would not work, since a scientific effort would need to be a civilian affair. The plan was modified, and the new laboratory would be a civilian one, run by the University of California under contract from the War Department. In the end, Rabi still did not go west, but did agree to serve as a consultant to the Manhattan Project.[52] Rabi attended the Trinity test in July 1945. The scientists working on Trinity set up a betting pool on the yield of the test, with predictions ranging from total dud to 45 kilotons of TNT equivalent (kt). Rabi arrived late and found the only entry left was for 18 kilotons, which he purchased.[53] Wearing welding goggles, he waited for the result with Ramsey and Enrico Fermi.[54] The blast was rated at 18.6 kilotons, and Rabi won the pool.[53]

Later life

In 1945, Rabi delivered the Richtmyer Memorial Lecture, held by the American Association of Physics Teachers in honor of Floyd K. Richtmyer, wherein he proposed that the magnetic resonance of atoms might be used as the basis of a clock. William L. Laurence wrote it up for The New York Times, under the headline "'Cosmic pendulum' for clock planned".[55][56][57] Before long Zacharias and Ramsey had built such atomic clocks.[58] Rabi actively pursued his research into magnetic resonance until about 1960, but he continued to make appearances at conferences and seminars until his death.[59][60]

Bardeen, Rabi, Heisenberg 1962
Rabi with fellow Nobel Prize laureates John Bardeen (left) and Werner Heisenberg (right) in 1962

Rabi chaired Columbia's physics department from 1945 to 1949, during which time it was home to two Nobel laureates (Rabi and Enrico Fermi) and eleven future laureates, including seven faculty (Polykarp Kusch, Willis Lamb, Maria Goeppert-Mayer, James Rainwater, Norman Ramsey, Charles Townes and Hideki Yukawa), a research scientist (Aage Bohr), a visiting professor (Hans Bethe), a doctoral student (Leon Lederman) and an undergraduate (Leon Cooper).[61] Martin L. Perl, a doctoral student of Rabi's, won the Nobel Prize in 1995.[62] Rabi was the Eugene Higgins professor of physics at Columbia but when Columbia created the rank of University Professor in 1964, Rabi was the first to receive such a chair. This meant that he was free to research or teach whatever he chose.[63] He retired from teaching in 1967 but remained active in the department and held the title of University Professor Emeritus until his death.[64] A special chair was named after him in 1985.[65]

A legacy of the Manhattan Project was the network of national laboratories, but none was located on the East Coast. Rabi and Ramsey assembled a group of universities in the New York area to lobby for their own national laboratory. When Zacharias, who was now at MIT, heard about it, he set up a rival group at MIT and Harvard. Rabi had discussions with Major General Leslie R. Groves, Jr., the director of the Manhattan Project, who was willing to go along with a new national laboratory, but only one. Moreover, while the Manhattan Project still had funds, the wartime organization was expected to be phased out when a new authority came into existence. After some bargaining and lobbying by Rabi and others, the two groups came together in January 1946. Eventually nine universities (Columbia, Cornell, Harvard, Johns Hopkins, MIT, Princeton, Pennsylvania, Rochester and Yale) came together, and on 31 January 1947 a contract was signed with the Atomic Energy Commission (AEC), which had replaced the Manhattan Project, that established the Brookhaven National Laboratory.[66]

HD.3F.010 (11086446676)
Rabi (seated, right) with fellow Nobel Prize laureates (standing left to right) Val Fitch, James Cronin, Samuel Chao Chung Ting and Chen-Ning Yang (seated, left)

Rabi suggested to Edoardo Amaldi that Brookhaven might be a model that Europeans could emulate. Rabi saw science as a way of inspiring and uniting a Europe that was still recovering from the war. An opportunity came in 1950 when he was named the United States Delegate to the United Nations Educational, Scientific and Cultural Organization (UNESCO). At a UNESCO meeting at the Palazzo Vecchio in Florence in June 1950, he called for the establishment of regional laboratories. These efforts bore fruit; in 1952, representatives of eleven countries came together to create the Conseil Européen pour la Recherche Nucléaire (CERN). Rabi received a letter from Bohr, Heisenberg, Amaldi and others congratulating him on the success of his efforts. He had the letter framed and hung it on the wall of his home office.[67]

Military matters

The Atomic Energy Act of 1946 that created the Atomic Energy Commission provided for a nine-man General Advisory Committee (GAC) to advise the Commission on scientific and technical matters. Rabi was one of those appointed in December 1946.[68] The GAC was enormously influential throughout the late 1940s, but in 1950 the GAC unanimously opposed the development of the hydrogen bomb. Rabi went further than most of the other members, and joined Fermi in opposing the hydrogen bomb on moral as well as technical grounds.[69] However, President Harry S. Truman overrode the GAC's advice, and ordered development to proceed.[70] Rabi later said:

I never forgave Truman for buckling under the pressure. He simply did not understand what it was about. As a matter of fact, after he stopped being President he still didn't believe that the Russians had a bomb in 1949. He said so. So for him to have alerted the world that we were going to make a hydrogen bomb at a time when we didn't even know how to make one was one of the worst things he could have done. It shows the dangers of this sort of thing.[71]

Oppenheimer was not reappointed to the GAC when his term expired in 1952, and Rabi succeeded him as chairman, serving until 1956.[72] Rabi later testified on Oppenheimer's behalf at the Atomic Energy Commission's controversial security hearing in 1954 that led to Oppenheimer being stripped of his security clearance. Many witnesses supported Oppenheimer, but none more forcefully than Rabi:

So it didn't seem to me the sort of thing that called for this kind of proceeding... against a man who has accomplished what Dr. Oppenheimer has accomplished. There is a real positive record... We have an A-bomb and a whole series of it, and we have a whole series of super bombs, and what more do you want, mermaids?[73][74]

Rabi was appointed a member of the Science Advisory Committee (SAC) of the Office of Defense Mobilization in 1952, serving as its chairman from 1956 to 1957.[75] This coincided with the Sputnik crisis. President Dwight Eisenhower met with the SAC on 15 October 1957, to seek advice on possible US responses to the Soviet satellite success. Rabi, who knew Eisenhower from the latter's time as president of Columbia, was the first to speak, and put forward a series of proposals, one of which was to strengthen the committee so it could provide the President with timely advice. This was done, and the SAC became the President's Science Advisory Committee a few weeks later. He also became Eisenhower's Science Advisor.[76] In 1956 Rabi attended the Project Nobska anti-submarine warfare conference, where discussion ranged from oceanography to nuclear weapons.[77] He served as the US Representative to the NATO Science Committee at the time that the term "software engineering" was coined. While serving in that capacity, he bemoaned the fact that many large software projects were delayed. This prompted discussions that led to the formation of a study group that organized the first conference on software engineering.[78]

Honors

In the course of his life, Rabi received many honors in addition to the Nobel Prize. These included the Elliott Cresson Medal from the Franklin Institute in 1942,[79] the Medal for Merit and the King's Medal for Service in the Cause of Freedom from Great Britain in 1948,[27] the officer in the French Legion of Honour in 1956,[80] Columbia University's Barnard Medal for Meritorious Service to Science in 1960,[81] the Niels Bohr International Gold Medal and the Atoms for Peace Award in 1967, the Oersted Medal from the American Association of Physics Teachers in 1982, the Four Freedoms Award from the Franklin and Eleanor Roosevelt Institute and the Public Welfare Medal from the National Academy of Sciences in 1985, and the Vannevar Bush Award from the National Science Foundation in 1986.[80][82] He was a Fellow of the American Physical Society, serving as its president in 1950, and a member of the National Academy of Sciences, the American Philosophical Society, and the American Academy of Arts and Sciences. He was internationally recognized with membership in the Japan Academy and the Brazilian Academy of Sciences, and in 1959 was appointed a member of the Board of Governors of the Weizmann Institute of Science in Israel.[27]

Death

Rabi died at his home on Riverside Drive in Manhattan from cancer on 11 January 1988.[65][59] His wife, Helen, survived him and died at the age of 102 on 18 June 2005.[83] In his last days, he was reminded of his greatest achievement when his physicians examined him using magnetic resonance imaging, a technology that had been developed from his ground-breaking research on magnetic resonance. The machine happened to have a reflective inner surface, and he remarked: "I saw myself in that machine... I never thought my work would come to this."[84]

Books

  • Rabi, Isidor Isaac (1960). My Life and Times as a Physicist. Claremont, California: Claremont College. OCLC 1071412.
  • Rabi, Isidor Isaac (1970). Science: The Center of Culture. New York: World Publishing Co. OCLC 74630.
  • Rabi, Isidor Isaac; Serber, Robert; Weisskopf, Victor F.; Pais, Abraham; Seaborg, Glenn T. (1969). Oppenheimer: The Story of One of the Most Remarkable Personalities of the 20th Century. Scribner's. OCLC 223176672.

Notes

  1. ^ Rigden 1987, pp. 17–21.
  2. ^ Rigden 1987, p. 27.
  3. ^ Ramsey 1993, p. 312.
  4. ^ Rigden 1987, p. 23.
  5. ^ Rigden 1987, pp. 27–28.
  6. ^ Rigden 1987, pp. 33–34.
  7. ^ Rigden 1987, pp. 35–40.
  8. ^ Rigden 1987, pp. 41–45.
  9. ^ Rabi 1927, pp. 174–185.
  10. ^ Rigden 1987, pp. 50–53.
  11. ^ Kronig & Rabi 1928, pp. 262–269.
  12. ^ Federal Reserve Bank of Minneapolis Community Development Project. "Consumer Price Index (estimate) 1800–". Federal Reserve Bank of Minneapolis. Retrieved 2 January 2019.
  13. ^ Rigden 1987, pp. 55–57.
  14. ^ Rigden 1987, pp. 57–59.
  15. ^ a b Rigden 1987, pp. 60–62.
  16. ^ Toennies et al. 2011, p. 1066.
  17. ^ Rabi 1929, pp. 163–164.
  18. ^ Rabi 1929b, pp. 190–197.
  19. ^ Rigden 1987, pp. 65–67.
  20. ^ Rigden 1987, pp. 66–69.
  21. ^ Rigden 1987, p. 104.
  22. ^ a b Rigden 1987, p. 71.
  23. ^ Rigden 1987, p. 72.
  24. ^ Rigden 1987, pp. 71–72.
  25. ^ a b Rigden 1987, p. 70.
  26. ^ Rigden 1987, p. 83.
  27. ^ a b c "Isidor Isaac Rabi - Biographical". Nobel Media. Retrieved 17 August 2012.
  28. ^ Rigden 1987, p. 80.
  29. ^ "Obituary: Victor William Cohen". Physics Today. 28 (1): 111–112. January 1975. Bibcode:1975PhT....28a.111.. doi:10.1063/1.3068792. ISSN 0031-9228. Archived from the original on 27 September 2013.
  30. ^ Rigden 1987, pp. 84–88.
  31. ^ Millman 1977, p. 87.
  32. ^ Rigden 1987, pp. 88–89.
  33. ^ Goldstein 1992, pp. 21–22.
  34. ^ Rigden 1987, p. 90.
  35. ^ Goldstein 1992, p. 23.
  36. ^ Rigden 1987, p. 116.
  37. ^ Goldstein 1992, pp. 33–34.
  38. ^ Rabi et al. 1939, pp. 526–535.
  39. ^ a b Kellogg et al. 1939, p. 728.
  40. ^ Rigden 1987, p. 115.
  41. ^ Breit & Rabi 1934.
  42. ^ Rabi, Kellogg & Zacharias 1934a, pp. 157–163.
  43. ^ Rabi, Kellogg & Zacharias 1934b, pp. 163–165.
  44. ^ Rigden 1987, pp. 112–113.
  45. ^ Rabi et al. 1938, p. 318.
  46. ^ Goldstein 1992, p. 36.
  47. ^ "BRL's Scientific Advisory Committee, 1940". U.S. Army Research Laboratory. Archived from the original on 1 December 2016. Retrieved 26 July 2016.
  48. ^ Conant 2002, pp. 209–213.
  49. ^ Rigden 1987, pp. 131–134.
  50. ^ Rigden 1987, pp. 135–135.
  51. ^ Rigden 1987, p. 143.
  52. ^ Hewlett & Anderson 1962, pp. 230–232.
  53. ^ a b Rhodes 1986, p. 656.
  54. ^ Rigden 1987, pp. 155–156.
  55. ^ Isidor I. Rabi, "Radiofrequency spectroscopy" (Richtmyer Memorial Lecture, delivered at Columbia University in New York, on 20 January 1945).
  56. ^ "Meeting at New York, January 19 and 20, 1945" Physical Review, vol. 67, pp. 199–204 (1945).
  57. ^ Laurence, William (21 January 1945). "'Cosmic pendulum' for clock planned" (PDF). The New York Times. p. 34. Retrieved 15 June 2012.
  58. ^ Rigden 1987, pp. 170–71.
  59. ^ a b Ramsey 1993, p. 319.
  60. ^ Rigden 1987, p. 15.
  61. ^ "Columbia Nobels". Columbia University. Archived from the original on 29 October 2012. Retrieved 16 June 2012.
  62. ^ "Martin L. Perl – Biographical". Nobel prize. Nobel Media. Retrieved 19 March 2016.
  63. ^ Rigden 1987, p. 68.
  64. ^ "Isidor Isaac "I. I." Rabi". Array of Contemporary American Physicists. Archived from the original on 17 October 2012. Retrieved 16 June 2012.
  65. ^ a b Berger, Marilyn (12 January 1988). "Isidor Isaac Rabi, a Pioneer in Atomic Physics, Dies at 89". The New York Times. pp. A1, A24.
  66. ^ Rigden 1987, pp. 182–85.
  67. ^ Rigden 1987, pp. 235–37.
  68. ^ Hewlett & Anderson 1962, p. 648.
  69. ^ Hewlett & Duncan 1969, pp. 380–85.
  70. ^ Hewlett & Duncan 1969, pp. 403–8.
  71. ^ Rigden 1987, p. 246.
  72. ^ Hewlett & Duncan 1969, p. 665.
  73. ^ Rigden 1987, p. 227.
  74. ^ Wellerstein, Alex (16 January 2015). "Oppenheimer, Unredacted: Part II". Restricted Data: the Nuclear Secrecy Blog. Retrieved 1 February 2015.
  75. ^ "White House Science Advisers". Array of Contemporary American Physicists. Archived from the original on 22 July 2013. Retrieved 16 June 2012.
  76. ^ Rigden 1987, pp. 248–51.
  77. ^ Friedman 1994, pp. 109–14.
  78. ^ MacKenzie 2001, p. 34.
  79. ^ "Isidor Isaac Rabi". The Franklin Institute. Retrieved 19 March 2016.
  80. ^ a b Ramsey 1993, p. 320.
  81. ^ "Rabi Awarded Barnard Medal". Physics Today. 13 (8): 52. August 1960. Bibcode:1960PhT....13h..52.. doi:10.1063/1.3057088. ISSN 0031-9228.
  82. ^ "Public Welfare Award". National Academy of Sciences. Retrieved 18 February 2011.
  83. ^ "Rabi, Helen Newmark". The New York Times. 21 June 2005. ISSN 0362-4331. Retrieved 23 January 2016.
  84. ^ Rigden 1987, pp. xxi–xxii.

References

External links

1898 in science

The year 1898 in science and technology involved some significant events, listed below.

1944 in science

The year 1944 in science and technology involved some significant events, listed below.

Albert Potter Wills

Albert Potter Wills (1873–1937) was an American physicist who researched magnetic materials and was the PhD advisor of the Nobel Prize winner Isidor Isaac Rabi.

During his career he investigated magnetic susceptibilities, magnetic shielding, magnetostriction, conduction of electricity through mercury vapor, and hydrodynamics. He also wrote a textbook on vector analysis.

Wills received his PhD from Clark University in 1897 under Arthur Gordon Webster with a thesis entitled: On the susceptibility of diamagnetic and weakly magnetic substances.

During 1898–1899 Wills worked at the University of Göttingen and the University of Berlin. During 1899–1902 he was at Bryn Mawr College and 1902–1903 at the Cooper Hewitt Laboratory. His final appointment, 1903–1937, was at Columbia University.

Francis Wheeler Loomis

Francis Wheeler Loomis (August 4, 1889 – February 9, 1976), born in Parkersburg, West Virginia, was an American scientist most widely known for his contributions in the field of physics. Loomis received his undergraduate degree and, in 1917, his PhD from Harvard University. His thesis was on thermodynamic measurements of mercury.Loomis was a Guggenheim Fellow in 1928 studying abroad at Zürich and Göttingen. In 1929, Loomis came to the University of Illinois at Urbana Champaign to become the head of the Department of Physics, a position he would retain until 1957. Loomis was challenged in bringing top-notch physics talent to a university in the rural Midwest. When approached by Loomis to join his staff, Isidor Isaac Rabi stated bluntly "I love subways and I hate cows." While building the department, Loomis attracted two-time Nobel recipient John Bardeen to join the staff, and had 1955 Nobel Prize winner Polykarp Kusch as a graduate student. Loomis was elected president of the American Physical Society and a member of the National Academy of Sciences in 1949.In World War I, Loomis served at the Aberdeen proving ground, where he was an Army Ordnance captain. During World War II, he was the associate head of the MIT Radiation Laboratory supporting the national defense and served a two-year period as the organizer of the MIT Lincoln Laboratory. The interruption of the war also required Loomis to restart his building of the physics department as two-thirds of the faculty he added in the 1930s moved elsewhere due to the many defense projects related to the war. Loomis founded the Control Systems Laboratory as a research center for national defense purposes during the Korean War. After the war ended and the work done there became unclassified, the facility was renamed the Coordinated Science Laboratory.At the University of Illinois at Urbana Champaign the main physics building was renamed the Loomis Laboratory of Physics posthumously in his honor.

I. I. Rabi Award

The I. I. Rabi Award, founded in 1983, is awarded annually by IEEE.

"The Rabi Award is to recognize outstanding contributions related to the fields of atomic and molecular frequency standards, and time transfer and dissemination."The award is named after Isidor Isaac Rabi, Nobel Prize winner in 1944. He was the first recipient of the award, for his experimental and theoretical work on atomic beam resonance spectroscopy.

Karl P. Cohen

Karl Paley Cohen (February 5, 1913 – April 6, 2012) was a physical chemist who became a mathematical physicist and helped usher in the age of nuclear energy and reactor development. He began his career in 1937 making scientific advances in uranium enrichment (isotope separation) as research assistant to Harold Urey, who discovered deuterium–the heavy isotope of hydrogen. Cohen worked within the Columbia group of physicists that included Harold Urey, Enrico Fermi, Leo Szilard, Isidor Isaac Rabi, John R. Dunning, Eugene T. Booth, A. Von Gross and others)–all pioneers of nuclear energy.

In 1942, the Manhattan Engineer District Project was established at Columbia University, and research began on various approaches for separating out the fissionable uranium isotope, U-235. Cohen developed the theory for the now-universal method of centrifugal isotope separation for enriching uranium, but was deeply involved also with the theory of gaseous diffusion, and literally wrote the book about both methods.Cohen and Urey were convinced that the Uranium Committee had made the wrong choice in 1942 by picking gaseous diffusion instead of centrifuges to produce U-235 for the atom bomb, and thus extended the war by a year. In 1944, Cohen left Columbia and went to work for Standard Oil Development Company to advise on nuclear energy.

Edward Teller’s autobiography Memoirs reflects positively on Cohen and Urey's centrifuge method for producing U-235 when he writes: “What if we had the atomic bomb a year earlier? The easiest and least expensive method of separating isotopes, a method used throughout the world today, is based on a centrifuge procedure that Harold Urey proposed in 1940. General Groves chose the diffusion method instead. Karl Cohen, Urey’s able assistant during that period, believes that Groves’ decision delayed the atomic bomb by a year.

“If Dr. Cohen is right, atomic bombs of the simple gun design might have become available in the summer of 1944 and, in that case, would surely have been used against the Nazis. Atomic bombs in 1944 might have meant that millions of Jews would not have died, and that Eastern Europe would have been spared more than four decades of Soviet domination.”

In 1948, Cohen became technical director for H.K. Ferguson's Atomic Energy Division, which was building the Brookhaven, Long Island, nuclear reactor. By 1952, Cohen was a founder, vice president and operating manager of Walter Kidde Nuclear Laboratories (WKNL), a privately funded research facility formed to commercially develop nuclear power. The lab’s principal contract was with the Atomic Energy Commission for R&D on reactors, and it established many industry standards, especially regarding slightly enriched uranium and water moderated reactor concepts.

Cohen’s long association with General Electric began in 1955, at first as a consultant, then as a manager involved with advanced engineering, advanced products, breeder reactor development, and operational planning. In 1973 Cohen was appointed Chief Scientist of G.E.'s commercial nuclear department. After his retirement in 1978, Cohen consulted for companies such as G.E., Boeing, and Exxon, and organizations such as the Institute for Energy Research, Scientists and Engineers for Secure Energy and the Electric Power Research Institute. Cohen also continued to be active on committees, at conferences, and in more informal peer review of technology and policy papers. He also taught intermittently at Stanford during this time, and donated his papers to the Stanford Library (M1798, Karl Cohen Papers). Karl Cohen passed away of natural causes in 2012. His last published paper was in Science in 2002, but due to his vast knowledge of the field, he continued to be a source of information on nuclear energy and nuclear policy for several years after the paper.

Cohen had a dream of bringing safe, abundant and affordable energy to the world. His paper published in 1992 in the International Journal of the Unity of the Sciences, Volume 5, Number 3 entitled "A Promise Unfulfilled" argues that before the potential of nuclear fission as a limitless source of energy for earth’s societies can be reached, there must first be disarmament and nuclear weapons must be destroyed.

List of Jewish American physicists

This is a list of famous Jewish American physicists.

For other famous Jewish Americans, see List of Jewish Americans.

Alexei Abrikosov, condensed matter physics, Nobel Prize (2003) (Jewish mother; naturalized citizen)

Ralph Alpher, background radiation, nucleosynthesis

John N. Bahcall, astrophysicist

Hans Bethe, nuclear physicist, Nobel Prize (1967) (Jewish mother)

Felix Bloch, nuclear physicist, Nobel Prize (1952) (naturalized citizen)

David Bohm, quantum physicist, philosopher of science

Niels Bohr, physicist

Gregory Breit, physicist

Samuel T. Cohen, physicist

Mildred Dresselhaus, physicist, National Medal Of Science, Kavli Prize, Presidential Medal of Freedom (Jewish)

Albert Einstein (German), theoretical physicist, Nobel Prize (1921) (naturalized citizen)

Jeremy England, biophysicist

Paul Sophus Epstein, theoretical physicist, quantum mechanics

Herman Feshbach, nuclear physicist

Richard P. Feynman, physicist, Nobel Prize (1965) (though he always refused to appear in lists such as this one and other lists or books that classified people by race )

David Finkelstein, physicist

James Franck, physicist, Nobel Prize (1925)

Edward Fredkin, digital physicist

Jerome Friedman, physicist, Nobel Prize (1990)

Murray Gell-Mann, quarks, Nobel Prize (1969)

Donald A. Glaser, bubble chamber, Nobel Prize (1960)

Sheldon Glashow, physicist, Nobel Prize (1979)

Roy Glauber, physicist, Nobel Prize (2005)

Herbert Goldstein, Columbia physicist, author of standard textbook on classical mechanics

Samuel Goudsmit, electron spin

Brian Greene, string theorist

David Gross, string theorist, Nobel Prize (2004)

Alan Guth, cosmic inflation

Eugene Guth, polymer physics, nuclear physics, solid state physics

Robert Herman, cosmology, background radiation, operations research

Robert Hofstadter, physicist, Nobel Prize (1961)

Robert Jastrow, physicist, astronomer, cosmologist

Herman Kahn, nuclear physicist

Theodore von Kármán, aeronautical engineer

Joseph B. Keller, mathematical physics, wave propagation, National Medal Of Science, Wolf Prize

Daniel Kleppner, atomic research

Walter Kohn, physicist, Nobel Prize (1998)

Rudolf Kompfner, engineer and physicist

Lawrence Krauss, theoretical physicist and cosmologist

Cornelius Lanczos, mathematical physicist

Rolf Landauer, physicist, information theory

Leon M. Lederman, physicist, Nobel Prize (1988)

David Morris Lee, superfluidity, Nobel Prize (1996)

Fritz London, quantum chemistry

Theodore Maiman, first operable laser

Albert A. Michelson, speed of light, Nobel Prize (1907)

Alexander Migdal, theoretical high energy physics (naturalized citizen)

Ben Roy Mottelson, physicist, Nobel Prize (1975)

Frank Oppenheimer, nuclear physicist (brother of Robert)

Robert Oppenheimer, nuclear physicist (brother of Frank)

Douglas D. Osheroff, superfluidity, Nobel Prize (1996)

Jeremiah P. Ostriker, astrophysicist

Abraham Pais, historian of science

Wolfgang Pauli, nuclear physicist, Nobel Prize (1945) (Jewish father, half-Jewish mother; naturalized citizen)

Arno Allan Penzias, background radiation, Nobel Prize (1978)

Martin Lewis Perl, physicist, Nobel Prize (1995)

H. David Politzer, physicist, Nobel Prize (2004)

Alexander Polyakov, theoretical high energy physics (naturalized citizen)

Martin Pope, physical chemist, Davy Medal (2006)

Isidor Isaac Rabi, physicist, Nobel Prize (1944) (naturalized citizen)

Simon Ramo, physicist, engineer

Mark G. Raizen, physicist, quantum physics

Sidney Redner, statistical physics

L. Rafael Reif, Venezuelan-born American electrical engineer, president of MIT

Frederick Reines, neutrino experiment, Nobel Prize (1995)

Burton Richter, physicist, Nobel Prize (1976)

Carl Sagan, astronomer and science popularizer

Arthur Schawlow, laser spectroscopy, Nobel Prize (1981) (Jewish father)

Melvin Schwartz, physicist, Nobel Prize (1988)

John Schwarz, string theorist

Julian Schwinger, quantum physicist, Nobel Prize (1965)

Emilio G. Segrè, anti-proton, Nobel Prize (1959) (naturalized citizen)

Mikhail Shifman, theoretical particle physics (naturalized citizen)

Michael F. Shlesinger

Lee Smolin, loop quantum gravity

Alan Sokal, Sokal affair

H. Eugene Stanley, econophysics, phase transitions, critical phenomena

Jack Steinberger, physicist, Nobel Prize (1988)

Otto Stern, physicist, Nobel Prize (1943)

Andrew Strominger, string theory

Leonard Susskind, string theory (Jewish father)

Leó Szilárd, nuclear physicist (naturalized citizen)

Edward Teller, nuclear physicist

Arkady Vainshtein, theoretical high energy physics (naturalized citizen)

Alexander Vilenkin, cosmology (naturalized citizen)

Steven Weinberg, electroweak force, Nobel Prize (1979)

Victor Frederick Weisskopf (1908–2002), physicist; during World War II, he worked at Los Alamos on the Manhattan Project to develop the atomic bomb, and later campaigned against the proliferation of nuclear weapons

Eugene Wigner, quantum physicist, Nobel Prize (1963)

Edward Witten, mathematical physicist, Fields Medal (1990), founder of M-Theory, only physicist to win Fields Medal, and currently the driving force behind theoretical/mathematical physics

George Zweig, quarks

List of Nobel laureates affiliated with the Institute for Advanced Study

This is a comprehensive list of Nobel Prize winners affiliated the Institute for Advanced Study in Princeton, New Jersey as current and former faculty members, visiting scholars, and other affiliates.

Of the 201 individuals who have received the Nobel Prize in Physics as of 2015, thirty-three have been affiliated with the IAS at some point in their career. Other Nobel laureates at the IAS comprise one winner of the Nobel Prize in Chemistry, two winners of the Nobel Prize in Physiology or Medicine, two winners of the Nobel Prize in Literature, and four winners of the Nobel Memorial Prize in Economic Sciences.Some, such as Isidor Isaac Rabi and Paul Berg, won the prize before they came to the Institute; others, such as Jack Steinberger and Richard Stone, won it after; and some, such as Wolfgang Pauli and T. S. Elliot, won a prize during their tenure at the institute. Some prizewinners, such as George Seferis and Albert Szent-Györgyi, were visiting scholars, only at the IAS for a few semesters or less; others, such as Einstein and Chen Ning Yang, were permanent faculty members who remained for many years.

List of spectroscopists

Articles about notable spectroscopists.

List of university professors at Columbia University

At Columbia University, the title of University Professor is the highest faculty rank reserved for a small number of its faculty who have made important contributions to their field of study. Created in 1964, University Professors serve the university as a whole rather than a specific Faculty or Department.

Niels Bohr International Gold Medal

The Niels Bohr International Gold Medal is an international engineering award. It has been awarded since 1955 for "outstanding work by an engineer or physicist for the peaceful utilization of atomic energy". The medal is administered by the Danish Society of Engineers (Denmark) in collaboration with the Niels Bohr Institute and the Royal Danish Academy of Sciences. It was awarded 10 times between 1955 and 1982 and again in 2013. The first recipient was Niels Bohr himself who received the medal in connection with his 70th birthday.

Norman Foster Ramsey Jr.

Norman Foster Ramsey Jr. (August 27, 1915 – November 4, 2011) was an American physicist who was awarded the 1989 Nobel Prize in Physics, for the invention of the separated oscillatory field method, which had important applications in the construction of atomic clocks. A physics professor at Harvard University for most of his career, Ramsey also held several posts with such government and international agencies as NATO and the United States Atomic Energy Commission. Among his other accomplishments are helping to found the United States Department of Energy's Brookhaven National Laboratory and Fermilab.

Pupin Hall

Pupin Physics Laboratories , also known as Pupin Hall, is home to the physics and astronomy departments of Columbia University in New York City and a National Historic Landmark. It was built in 1925-1927 to provide more space for the Physics Department which had originally been housed in Fayerweather Hall, and named for Serbian physicist Mihajlo Idvorski Pupin, who graduated with honors in 1883 at Columbia College, after his death in 1935. The building is located on the south side of 120th Street, just east of Broadway. It has been named a National Historic Landmark for its association with experiments relating to the splitting of the atom, achieved in connection with the later Manhattan Project.

By 1931, the building which later became Pupin Hall was a leading research center. During this time Harold Urey (Nobel laureate in Chemistry) discovered deuterium and George B. Pegram was investigating the phenomena associated with the newly discovered neutron. In 1938, Enrico Fermi escaped fascist Italy after winning the Nobel prize for his work on induced radioactivity. In fact, he took his wife and children with him to Stockholm and immediately emigrated to New York. Shortly after arriving he began working at Columbia University with Dr. John Dunning. His work on nuclear fission, together with I. I. Rabi's work on atomic and molecular physics, ushered in a golden era of fundamental research at the university. One of the country's first cyclotrons was built in the basement of Pupin Hall by John R. Dunning, where it remained until 2007. The building's historic significance was secured with the first splitting of a uranium atom in the United States, which was achieved by Enrico Fermi in Pupin Hall on January 25, 1939, just 10 days after the world's first such successful experiment, carried out in Copenhagen, Denmark.

Pupin Hall is named after Mihajlo Idvorski Pupin (also known as Michael I. Pupin), a Serbian-American scientist and graduate of Columbia. Returning to the university's engineering school as a faculty member, he played a key role in establishing the department of electrical engineering. Pupin was also a brilliant inventor, developing methods for rapid x-ray photography and the "Pupin coil," a device for increasing the range of long-distance telephones. After his death in 1935, the university trustees named the newly constructed physics building the "Pupin Physics Laboratories" in his honor.

The building was declared a National Historic Landmark in 1965. In 2009 the American Physical Society named Pupin Hall a historic site and honored Isidor Isaac Rabi for his work in the field of magnetic resonance.

Rabi

Rabi may refer to:

Rabi crop, spring harvest in South Asia

Rabi cycle, in physics is the cyclic behavior of a two-state quantum system in the presence of an oscillatory driving field

Rabi Island, volcanic island in northern Fiji

Rabi Council of Leaders, municipal body administering Rabi Island

Rabi problem, concerns the response of an atom to an applied harmonic electric field, with an applied frequency very close to the atom's natural frequency

Rabi, or Lavi, a character from the D. Gray-man manga series

Rabi, one of the three main characters from Madō King Granzort

Rabī or Lavie, character from the Sgt. Frog anime series

Rábí, castle in the Czech Republic

Rabí, village in the Czech Republic

Räbi, village in Estonia

Rabi, Panchthar, a Village Development Committee in Nepal

Rabi cycle

In physics, the Rabi cycle (or Rabi flop) is the cyclic behaviour of a two-level quantum system in the presence of an oscillatory driving field. A great variety of physical processes belonging to the areas of quantum computing, condensed matter, atomic and molecular physics, and nuclear and particle physics can be conveniently studied in terms of two-level quantum mechanical systems, and exhibit Rabi flopping when coupled to an oscillatory driving field. The effect is important in quantum optics, magnetic resonance and quantum computing, and is named after Isidor Isaac Rabi.

A two-level system has two possible levels, and if they are not degenerate (i.e. equal energy), the system can become "excited" when it absorbs a quantum of energy. When an atom (or some other two-level system) is illuminated by a coherent beam of photons, it will cyclically absorb photons and re-emit them by stimulated emission. One such cycle is called a Rabi cycle and the inverse of its duration the Rabi frequency of the photon beam. The effect can be modeled using the Jaynes–Cummings model and the Bloch vector formalism.

Rabi resonance method

Rabi resonance method is a technique developed by Isidor Isaac Rabi for measuring the nuclear spin. The atom is placed in a static magnetic field and a perpendicular rotating magnetic field.

We present a classical treatment in here.

Ramsey interferometry

Ramsey interferometry, also known as Ramsey–Bordé interferometry or the separated oscillating fields method,

is a form of atom interferometry that uses the phenomenon of magnetic resonance to measure transition frequencies of atoms. It was developed in 1949 by Norman Ramsey, who built upon the ideas of his mentor, Isidor Isaac Rabi, who initially developed a technique for measuring atomic transition frequencies. Ramsey's method is used today in atomic clocks and in the S.I. definition of the second. Most precision atomic measurements, such as modern atom interferometers and quantum logic gates, have a Ramsey-type configuration.

A modern interferometer using a Ramsey configuration was developed by French physicist Christian Bordé and is known as the Ramsey–Bordé interferometer. Bordé's main idea was to use atomic recoil to create a beam splitter of different geometries for an atom-wave. The Ramsey–Bordé interferometer specifically uses two pairs of counter-propagating interaction waves, and another method named the "photon-echo" uses two co-propagating pairs of interaction waves.

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