Background-free fluorescence detection of cold atoms in a two-color magneto-optical trap.
A two-color magneto-optical trap (MOT) for trapping cesium (Cs) atoms is experimentally realized. This two-color MOT employs the radiation forces due to photon scattering from the Cs 6P(3/2) F' = 5 - 8S(1/2) F" = 4 excited-state transition, which replaced one pair of the three pairs of cooling/trapping laser beams operating on a single-photon red detuning to the Cs 6S(1/2) F = 4 - 6P(3/2) F' = 5 cycling transition in a standard six-beam Cs MOT, and can cool and trap atoms on both the red-detuning and blue-detuning sides of the two-photon resonance. Employing the two-color MOT, the background-free fluorescence detection of trapped atoms has been demonstrated. This technique will be useful for observation of weak fluorescence signal radiated from single atoms in MOT.
State Key Laboratory of Quantum Optics and Quantum Optics Devices, Shanxi University, and Institute of Opto-Electronics, Shanxi University, Taiyuan 030006, Shanxi Province, China.
Baodong
B
Yang
Qiangbing
Q
Liang
Jun
J
He
Junmin
J
Wang
D004867:Equipment Design; D019544:Equipment Failure Analysis; D036641:Microscopy, Fluorescence, Multiphoton / Q000295:instrumentation*; D052898:Optical Tweezers