非相干泵浦对原子系统位相相关吸收性质的影响

研究发现在具有真空诱导相干性的开放和封闭ladder 型原子系统中,探测场和驱动场之间相对位相对吸收性质有重要的调制作用,同时非相干泵浦对位相相关的吸收性质有显著的影响.在这两种系统中,通过调节非相干泵浦,可以实现从吸收到增益和从粒子数反转激光到无粒子数反转激光的转化,并可获得最大的无反转激光增益.但是,当非相干泵浦不存在时,对相对位相的任意值,在封闭系统中只出现吸收而不能得到无反转激光增益；然而在开放系统中,对于适当的相对位相值甚至可以产生比有非相干泵浦时更大的无反转激光增益.

Effect of Incoherent Pumping on Phase-dependent Absorption Property of Atomic Systems

In the open and closed ladder systems with vacuum induced coherence,it is found that the relative phase between the probe and driving fields has an important manipulation role on the absorption property, while the incoherent pumping has a considerable effect on the phase-dependent absorption property. In both systems, by adjusting the incoherent pumping the switching from absorption to gain and from lasing with inversion to lasing without inversion can be realized and the largest inversionless gain can be gotten. However, when the incoherent pumping is absent, for any value of the relative phase, lasing without inversion still can not be obtained in the closed system but it is able in the open system; and in the open system, for suitable values of the relative phase, inversionless gain gotten when the incoherent pumping is absent is obviously larger than that obtained when the incoherent pumping presents.