School on. Cold Atoms and Molecules. and. Applications in Spectroscopy. University of Tunis. Tree

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1 School on Cold Atoms and Molecules and Applications in Spectroscopy University of Tunis Your Scientific Family Tree Daniel Kleppner MIT/Harvard Center for Ultracold Atoms 19 March, 2015

2 Our Scientific Family Tree

3 A Family Tree

4 A few thoughts on Family Trees in Science Our family tree starts about the time that quantum mechanics wascreated in the mid 1920s.

5 The family tree is organized around the Nobel Prizes in our field. This has both advantages and disadvantages Advantages: it includes most of the significant advances and yet has a reasonable number of branches Disadvantages: it gives undue emphasis to the Nobel Prize. The Prize always marks an important advance but not every important advance is awarded the Prize. Also, the time between a discovery and the Prize can be lengthy. An unusual feature of our tree is that it comes with an INTRODUCTION.

6 INTRODUCTION Albert A.Michelson Michelson-Morley experiment, 1887

7 Michelson s life makes a remarkable story that is invaluable for understanding our scientific heritage. He was born in Poland in 1852 and...

8 In addition to carrying out the Michelson-Morley Experiment, A. A. Michelson measured the speed of light to a few parts in 10 4 while a young naval officer, and continued his measurements until the day he died developed techniques for measuring large distances in terms of the wavelength of light, creating the first atomic metrological standard measured the width of spectral lines, discovered pressure broadening, made the first measurements of the mean speeds of atoms, discovered fine structure...

9 THE Hydrogen fine structure visibility of fringes The Visibility of Fringes Balmer--alpha Balmer-beta Balmer--beta reconstructed spectrum Difference in path length distance of interferometer mirror ----> (data plotted by Michelson)

10 Measurements of the speeds of atoms from the Doppler broadening of their spectral lines.

11 A. A. MICHELSON ( continued) Invented Fourier transform spectroscopy Discovered how to use optical coherence and made the first measurement of the diameter of a star Created a discipline that is esteemed in our field: PRECISION MEASUREMENTS AND FUNDAMENTAL CONSTANTS,

12 In 1907, A.A. Michelson was awarded the Nobel Prize in Physics, for his optical precision instruments and his spectroscopic and metrological investigations carried out with their aid for more on Michelson, see Master Michelson s Measurement, D. Kleppner, Physics Today, August. 2007, p. 9.

13 To continue: What is the name of our field? Before 1900 it was simply called Physics In 1947 the APS named it Electron and Atomic Physics In 1983 the APS renamed it Atomic, Molecular, and Optical Physics or AMO Physics In the last few decades, the field changed so rapidly that it really deserves a new name.

14 Whatever its name, our field today started with the birth of quantum mechanics in the mid 1920s.

15 The founding event for our field can be taken to be the molecular beams studies by Otto Stern, Otto Stern, Professor, University of Hamburg, Nobel Prize: 1943 "for his contribution to the development of the molecular ray method and his discovery of the magnetic moment of the proton

16 Otto Stern carries out atomic kinetic studies on the velocities of molecules, in Hamburg. from Nobel Prize lecture

17 Stern s goal was to measure the speeds of atoms The speed was found from the distance atoms fel under gravity while traveling horizontally for two meters. Note the absence of slow atoms. (Stern and Estermann, 1946).

18 Without Stern s molecular beams research there might have been no Molecular Beam Magnetic Resonance (Nobel Prize 1944) Discovery of electron g-factor anomaly (Nobel Prizes 1949) Optical pumping (Nobel Prize, 1969) Molecular beam scattering (Nobel Prizes, Chemistry, 1986) Zeeman slowing (Nobel Prize, 1997) Rydberg atom methods for cavity QED (Nobel Prize, 2012)

19 But Stern is best known for the discovery of Spatial Quantization: The Stern-Gerlach Experiment, 1924

20 1924- The Stern-Gerlach experiment Source of silver atoms slits deflecting detector magnet (chemical) Observed pattern of atoms. profile of deflecting magnet

21 The next big step in our field was made by a young novice : I. I. Rabi I.I. Rabi starts graduate study in U.S. at Columbia University. He is asked to give a seminar on the Stern-Gerlach experiment Rabi travels to Europe to work with Bohr. Bohr sends him to work with Pauli in Hamburg. Rabi meets Stern and suggests an experiment. Stern invites Rabi to do it. Rabi becomes an experimenter Rabi studies molecular refraction

22 1928-Rabi Demonstrates Magnetic Deflection in Uniform Field I. I. Rabi, Z. Physik, 54, 190 (1929) Rabi moves to Columbia University

23 1931- Rabi collaborates with Gregory Breit and creates the Breit-Rabi formula for the hyperfine energies of a one-electron atom in a magnetic field. Nuclear spin = 1/2 Nuclear spin = 3/2

24 Various deflection and refocusing schemes pursued in Rabi lab. source detector A magnet C magnet B magnet An atom that changes its state in the C magnet does not get to the detector J. M. B. Kellogg and S. Millman, Rev. Mod. Physics. 18, 323 (1946)

25 1936- Attempt to change direction of spin by passage through a field that rotates as atom flies through. The T Field J. M. B. Kellogg, I. I. Rabi and J. R. Zacharias, Phys. Rev. 50, 472 (1936)

26 1937, March- Rabi presents theory for spin-state transitions in a field whose direction changes in time. 1937, Fall- CornelisGorter visits from Amsterdam and suggests using an oscillating field

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28 The first radio frequency resonance curve Rabi resonance of Li-7

29 I.I. Rabi was awarded the Nobel Prize in for his resonance method for recordingthe magnetic properties of atomic nuclei". I. I. Rabi,

30 A few immediate consequences of Molecular Beam Magnetic Resonance

31 Nobel Prize 1952 for the invention of Nuclear Magnetic Resonance Felix Bloch Edward M.Purcell

32 Consequences from the discovery of NMR Nuclear physics: A new technique for measuring magnetic properties of nuclei Chemistry: a standard technique for studying molecular structure Medicine: MRI: a method to image the body and observe brain activity Metrology: a new technique for measuring magnetic fields

33 Nobel Prize 1955 for their fundamental work in quantum electrodynamics, with deep-ploughing consequences for the physics of elementary particles Willis Lamb Polykarp Kusch

34 Lamb and Kusch showed that two predictions of the Dirac theory of the electron were wrong: 1. Prediction that the 2S 1/2 and 2P 1/2 states of hydrogen have exactly the same energy. Not true: the difference is called the Lamb Shift. Size~ 1480 MHz 2. Prediction that the g-factor of the electron is exactly 2. Not true: the difference is called the g-factor anomaly. Size~ 1 part in a thousand Consequences...

35 Nobel Prize 1965 Sin- ItiroTomanag a Julian Schwinger Richard Feynman

36 Nobel Prize 1965 For their fundamental work in quantum electrodynamics, with deep-ploughing consequences for the physics of elementary particles" Consequences...

37 Consequences of the 1965 Nobel Prize: Creation of QED, the Theory of Relativistic Quantum Electrodynamics. This is now the most accurately tested theory in Physics. Theory and experiment agree to a few Parts in

38 Nobel Prize 1964 Citation: For the invention of the maser and laser Charles H. Townes Nicolay G. Basov Alesander M. Prokhorov Consequences of the maser...

39 H.M Goldenberg, D. Kleppner, and N.F. Ramsey Phys. Rev. Lett. 5, 361 (1960)

40 Consequences of the invention of the Laser Problem: The laser is a TRANSFORMATIVE technology A transformative technology effects broad A transformative technology effects broad areas of society. Such a change cannot be summarized. Nevertheless, it deserve a few words.

41 Nobel Prize 1966 Alfred Kastler For the discovery and applications of optical pumping

42 Jean Brossel collaborated with Alfred Kastler in the discovery of Optical Pumping Jean Brossel Consequences...

43 Consequences of the invention of Optical Pumping Provided a new field for the study of light-atom interactions Led to new kinds of atomic clocks and magnetometers Launched Claude Cohen-Tannoudji on the path that led to his Dressed Atom Theory Is a critical technique for all atom-cooling methods

44 Nobel Prize 1981 Nicolaas Bloembergen Non linear spectroscopy Arthur L. Schawlow Laser spectroscopy

45 Nobel Prize 1981 Nicolaas Bloembergen pioneered the non-linear optics theories provide the underpinning for contemporary atom optics, not to mention modern communications. Arthur L. Schawlow was the co inventor of the laser, with Charles Townes

46 Nobel Prize 1989 Norman F. Ramsey Hans G. Dehmelt WolfgangPaul

47 Nobel Prize 1989 Dehmeltinvented single-electron spectroscopy and applied it to measure the electron g-factor to about a part in Later work by Gabrielse substantially Improved this. Paul invented a new type of mass spectrometer based on confining ions with static and oscillating electric fields. It is now used for optical atomic clocks and quantum entangements studies.

48 Nobel Prize 1989 Norman Ramsey: for the separated oscillatory field method (SOF) and the hydrogen maser SOF was invented in It was the enabling technology that made atomic clocks possible. Today it plays a role in most atomic studies of quantum entanglement, for instance those of Serge Haroche (N.P. 2012). The hydrogen maser has became a workhorse frequency standard for the GPS and for Very Long Baseline Interferometry for astronomers.

49 Separated Oscillatory Field (1949)

50 First atomic clock, Louis Essen and Jack Perry, NPL, Teddington, England, 1954 Essen and Perry, 1955

51 Portable atomic clock Portable atomic beam Jerald Zacharias MIT, 1954

52 First Atomichron Jerald Zacharias and R. I. Daly, October, 1956 P. Forman, Proc. IEEE, 73, July, 1985

53 Nobel Prize 1997 Steven Chu 1948 Claude Cohen- Tannoudji William D. Phillips for development of methods to cool and trap atoms with laser light".

54 Nobel Prize 2001 Eric A. Cornell 1961 Wolfgang Ketterle 1957 Carl E. Wieman 1951 "for the achievement of Bose-Einstein condensation in dilute gases of alkali atoms, and for early fundamental studies of the properties of the condensates

55 Comment on the invention of laser cooling and the creation of atomic quantum fluids. These advances are causing a consilience between atomic physics and condensed matter physics. Such an event holds the promises of being TRANSFORMATIVE.

56 Nobel Prize 2005 Roy J. Glauber 1925 John L Hall 1934 Theodor Hänsch 1941 Glauber: for the quantum theory of quantum coherence Hall and Hänsch: for precision spectroscopy including the optical comb method

57 Nobel Prize 2012 Serge Haroche 1944 David J. Wineland 1944 for ground-breaking experimental methods that enable measuring and manipulation of individual quantum systems"

58 Some comments on this history of our field The ultimate consequences of a discovery are likely not to be recognized by the investigator or even by the Nobel Prize committee! The time for a fundamental advance to become useful for new research can be short but for practical applications It is likely to be long, typically more than 20 years. There are as many opportunities for new discoveries with important scientific and practical consequences as ever.

59 In conclusion, I wish you Good Luck! and so do all my colleagues at the MIT/Harvard Center for Ultracold Atoms