Atom Cooling and Trapping

Ashkin [9.435] and illustrated in Fig. 9.72a. Optical forces for confining had already been suggested by Letokhov [9.436]. An atom feels a force directed towards the volume of highest hght intensity because of a dipole force (the light-induced electric dipole feels the electric force gradient). 

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Two recent reviews recount subsequent research in the physics of neutral-atom cooling and trapping [3, 4],... 

W. Phillips, J. Prodan, H. Metcalf, J. Opt. Soc. Am. B 1751(1985). This review article (in a special issue of JOSAB) contains detailed description of many aspects of neutral atom cooling and trapping. 

Phillips W D 1998 Laser cooling and trapping of neutral atoms Rev. Mod. Rhys. 70 721... 

Metcalf H and van der Straten P 1994 Cooling and trapping of neutral atoms Phys. Rep. 244 203-86... 

W. D. Phillips (NIST, Gaithersburg) development of methods to cool and trap neutral atoms with laser light. 

Recent advances in the production and storage of positrons and antiprotons have made it possible to think about the synthesis of atomic antimatter in the laboratory. Parallely, contemporary advances in cooling and trapping atoms have led to an unprecedented accuracy of spectroscopic measurments. The important difference between the spectroscopy of atoms and antiatoms is that in the latter case, because of annihilation, the sample must be isolated from the surrounding environment. 

Ultracold neutral plasmas may be produced by laser cooling and trapping of different types of neutral atoms [105] such as calcium, strontium, rubidium, cesium etc., by photoionizing Bose condensates [106] and also by spontaneous ionization of dense Rydberg atoms [107,108]. A review on ultracold neutral plasmas due to Killan et al. [61] gives an excellent disposition on the subject. 

With only one exception, every experiment on BEC has employed laser cooling and trapping methods to create a gas of cold atoms. The exception is hydrogen. The recoil energy of hydrogen is so large that the gas cannot be cooled below a few millikelvin, with densities far from the transition. (The Amsterdam group... 

The rapid development of techniques for cooling and trapping atoms using laser light has created a new subfield of atomic physics. Research opportunities include the study of matter at ultra low temperature, ultra precise atomic spectroscopy and the study of light-matter interaction in a new quantum regime. 

MOT Magneto Optical Trap. The well established technique for Doppler cooling and trapping of a thermal cloud of cold atoms. 

It is also a pleasure to recognize one of the invited speakers. Dr. William D. Phillips, who was awarded the 1997 Nobel Prize in Physics for development of methods to cool and trap atoms with laser light. ... 

In this section I hope to show how the sensitivity of laser spectroscopy is exploited to obtain data on very low concentrations of atoms. In particular I will start off by considering a few laser atomic beam studies aimed at measuring optical isotope shifts and show how short-lived nuclei can be studied in this way. I shall also mention how it is possible to beat the natural linewidth and obtain supernatural spectra . The discussion of laser studies at low atomic concentrations then leads me onto consider experiments on laser cooling and trapping of atoms and ions. In this context I will also mention some experiments using the shelved electron idea to detect very weak transitions. Finally, I will say something about Rydberg atoms and the effects of atoms near metallic surfaces. 

Figure 10. Laser cooling and trapping of neutral sodium atoms.

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