Open AccessRole of selective excitation of dressed populations in lasing without inversion
Author(s) -
Zhenhua Wang,
Xiangming Hu
Publication year - 2004
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.53.2569
Subject(s) - lasing threshold , excitation , population inversion , excited state , physics , atomic physics , population , laser , optics , quantum mechanics , demography , sociology
Exemplifying the three-level systems in the V configuration, we investigate the role of selective excitation of dressed populations in lasing without inversion. Incoherent driving field transfers population from either of the dressed states to excited state when the level spacing between dressed states produced by the coherent field is much larger than the spectral width of the incoherent driving field. With atomic decay pathwaysunidirectional channel of population transfer is formed and selective excitation of dressed populations is established. Employing selective excitation of dressed populationsthree severe limits are relaxed. Firstit is no longer required that the decay rate of the low-frequency driving transition is larger than that of high-frequency laser transition. Secondthe threshold for incoherent driving rate is remarkably lowered. Thirdlinear gain of the laser without inversion is no longer inversely proportional to the coherent driving field intensity, and the gain is significantly enhanced.