Effects of relative phase on transient evolution in an open resonant ladder-type atomic system  

作　　者：杨艳玲 刘中波 王蕾 仝殿民 樊锡君 

机构地区：[1]College of Physics and Electronics,Shandong Normal University [2]School of Physics and Microelectronics,Shandong University

出　　处：《Chinese Physics B》2009年第3期1054-1060,共7页中国物理B（英文版）

基　　金：supported by the Natural Science Foundation of Shandong Province,China (Grant No Y2006A21);the National Natural Science Foundation of China (Grant No 10675076)

摘　　要：In an open ladder-type resonant atomic system, variation in relative phase between probe and driving fields does not affect the transient evolution of populations, but it has remarkable effects on gain and dispersion of the probe field. No matter whether an incoherent pump is present or absent, transient and stationary gains without inversion （GWI） always can be obtained by choosing an appropriate value of the relative phase. When the incoherent pump is absent, the values of transient and stationary GWIs are much larger and the time interval required to reach the stationary value is longer than those when the incoherent pump is present. Varying the exit rate and the ratio between injection rates can obviously change the phase-dependent GWI. In addition, in the transient evolution process, the phenomenon of high dispersion （refractive index） without absorption occurs at some values of relative phase. In the corresponding closed system, the stationary GWI can be obtained by choosing an appropriate value of relative phase only when incoherent pump exists, moreover the gain is smaller than that in the open system.In an open ladder-type resonant atomic system, variation in relative phase between probe and driving fields does not affect the transient evolution of populations, but it has remarkable effects on gain and dispersion of the probe field. No matter whether an incoherent pump is present or absent, transient and stationary gains without inversion （GWI） always can be obtained by choosing an appropriate value of the relative phase. When the incoherent pump is absent, the values of transient and stationary GWIs are much larger and the time interval required to reach the stationary value is longer than those when the incoherent pump is present. Varying the exit rate and the ratio between injection rates can obviously change the phase-dependent GWI. In addition, in the transient evolution process, the phenomenon of high dispersion （refractive index） without absorption occurs at some values of relative phase. In the corresponding closed system, the stationary GWI can be obtained by choosing an appropriate value of relative phase only when incoherent pump exists, moreover the gain is smaller than that in the open system.

关 键 词：open system relative phase transient evolution gain without inversion 

分 类 号：O431.2[机械工程—光学工程] O562.1[理学—光学]