开放V型无反转激光系统相位涨落的影响

通过对从开放的V型双泵浦系统的定态解析解得到的数值计算结果的分析表明:1)驱动场相位将涨落导致一个有限线宽;一般说来,被探测场耦合的上下两能级间的粒子数差随线宽的增加而减小,当线宽增加到一定值时,系统将发生从传统的反转激光到无反转激光的转化;线宽的增加将使无反转激光增益降低;当线宽不为零时,仍可产生无吸收高色散(折射率)2)线宽变化对增益、色散和粒子数差影响的性质和大小与系统其它参量的取值密切相关,只有适当选择线宽和系统其它参量的值才能获得最大的无反转激光增益和无吸收高色散(折射率).

The Effects of Phase Fluctuation in an Open V-type Inversionless Lasing System

By analyzing the numerical calculation results from the stationary analytical solution of an open V-type system with two pumps, this paper shows that: 1) The phase fluctuation of the driving field will produce a finite line-width; generally speaking, the population difference between the upper and lower levels coupled by the probe field decreases with the line-width increasing, at some value of the line-width, a change from conventional inversion lasing to inversionless lasing occurs; increase of the line-width will make the gain of inversionless lasing declining; when the line-width doesn’t equal to zero, the system can still generate a large refractive index along with zero absorption.2) The property and size of the effect produced by the line-width varying on the gain, dispersion and population difference are tightly relative to the values of the other parameters of the system;the maximum gain of inversionless lasing and a large refractive index along with zero absorption only can be obtained when values of the linewidth and other parameters of the system are suitably selected.