利用数值计算结果,研究了具有自发辐射诱导相干的开放v型三能级原子系统中的传播效应.研究表明:改变探测场和驱动场之间的相对位相对无反转激光(LWI)增益和强度随传播距离的变化即空间演化具有重要的影响;而原子的注入速率比(S)和退出速率(r0)的改变将对位相相关的LWI增益和强度的空间演化产生明显的调制作用.在S(r0)的一定取值范围内,S(r0)的值越大,LWI增益和强度越大且强度达到极大值需要的传播距离越长;相应封闭系统中LWI增益和强度的最大值及能产生增益的传播距离都小于开放系统.Doppler效应对LWI增益和强度的空间演化也具有明显的影响,存在Doppler效应时得到的LWI增益和强度明显小于无Doppler效应时的值.
The propagation effect in an open V-type three-level atomic system with spontaneously generated coherence is studied by numerical calculation. The results show that changing the relative phase between the probe and driving field has an important ef- fect on variations of gain and intensity of lasing without inversion (LWI) with propagation distance, i.e. spatial evolution; variation of ratio (S) between the atomic injection rate and atomic exit rate (to) has a remarkable modulation role in phase-dependent spatial evolution. In a certain range of S (r0), with value of S (r0) increasing, LWI gain and intensity increase and the propagation distance needed for reaching an intensity maximum value becomes longer; In a corresponding closed system, the maxima of LWI gain, intensity and the propagation distance along which the gain can be produced are smaller than in an open system. The Doppler effect also has an obvious influence on spatial evolutions of LWI gain and intensity, values of LWI gain and intensity are smaller in the presence of Doppler effect than in the absence of Doppler effect.