V Coherent Population Trapping in Laser Spectroscopy

Alexey V. Akimov, N. Kolachevsky, А. В. Соколов +5 more

A new source of the bichromatic laser field with a stable mean value of the difference frequency is used to study coherent population trapping (CPT). A high stability of the difference phase of the fields of the radiation source is achieved by phase locking the radiation frequency of two semiconductor lasers to longitudinal modes of a femtosecond laser. The first experimental results on the spectroscopy of CPT resonances in rubidium are presented. The possibility of using the new method for spectroscopy of CPT resonances in rare-earth atom vapours is discussed.

Bryan J. Dalton, P. L. Knight

Xianghui Qi, Wenlong Chen, Lin Yi +2 more

A new source of two diode laser beams, spatially separated but optically phase-locked with each other, is used to study the modulation transfer spectroscopy of coherent population trapping resonance (CPT). The spectrum for the (87)Rb D2 line is obtained with narrow linewidth and high signal-to-noise ratio, and analyzed with different experimental parameters. A theoretical analysis of the CPT modulation transfer spectra is deduced from the density matrix equation of motion, and found to be in good agreement with the experimental results.

Boris G. Matisov, I. E. Mazets

Koji Motomura, Masaharu Mitsunaga

High-resolution spectroscopy of hyperfine Zeeman components in a sodium atomic vapor has been performed by a coherent population trapping (CPT) technique. The measurement features the simple configuration of a single laser source with a frequency-swept double-pass acousto-optic modulator. Well-resolved CPT dip signals in the presence of longitudinal or transverse static magnetic fields can be nicely explained by a theory based on two-photon resonance.