Transient Inversionless Amplification in Rubidium Atoms by Laser Frequency-Switching

Noritsugu Shiokawa, Yoshio Toril, Takuya Hirano +1 more

Yongqing Li, W. H. Burkett, Min Xiao

We report observation of coherent transient amplification that is due to free-induction decay and optical nutation in inhomogeneously broadened rubidium atoms by a sudden switch of diode-laser frequency. An amplification coefficient of 2.2 x 10(-2) cm(-1) is observed when the diode-laser frequency, initially tuned to the blue side of the Doppler-broadened absorption profile, is switched to be out of resonance by application of a step-function pulsed injection current. The transition from free-induction decay to optical nutation is observed and discussed.

Igor M. Beterov, A. Dudnikov, I. I. Ryabtsev

Noritsugu Sbiokawa, Yoshio Torii, Takuya Hirano +1 more

Complete transparency via effect of quantum interference in a A-type three-level atomic system was observed by using laser-cooled rubidium atoms. We also demonstrated inversionless amplification of weak probe laser in this system.

Yifu Zhu, Ji Lin, Paul Sanchez

А. А. Черненко

The results of theoretical investigations of the line shape for the absorption (amplification) of a weak optical signal in the proximity of the system of autoionization atomic levels are reported. The best conditions and regions of existence of the inversionless amplification in the proximity of transitions from these atomic levels are determined depending on the energy defect between them, the Fano parameters, and the generalized Rabi frequencies, as well as on the incoherent pumping power. The problem of dynamics of atomic level occupancy for the pulse excitation is solved. It is demonstrated that the effect of the inversionless amplification for the transient mode can considerably exceed its own steady-state value.