标题： 逆Y型四能级系统中的电磁诱导透明性 显示英文标题

标题： Electromagnetically induced transparency in an inverted Y-type four-level system

摘要： 弱探测激光与由两个额外相干场驱动的倒Y型四能级原子系统的相互作用被理论研究。 在相干耦合场的影响下，探测激光的稳态线性电 susceptibility 显示，根据耦合激光的幅度和失谐情况，系统可以具有单个或双个电磁诱导透明窗口。 与探测激光的群速度相关的折射率指数可以通过耦合场在两个透明窗口中被控制。 当两个耦合激光处于共振时，在单个透明窗口内，探测场的传播可以从共振附近的超光速切换到共振时的亚光速。 这为量子信息处理提供了一种潜在的应用。 我们提出一个原子$^{87}Rb$系统用于实验观察。 显示英文摘要

摘要： The interaction of a weak probe laser with an inverted-Y type four-level atomic system driven by two additional coherent fields is investigated theoretically. Under the influence of the coherent coupling fields, the steady-state linear susceptibility of the probe laser shows that the system can have single or double electromagnetically induced transparency windows depending on the amplitude and the detuning of the coupling lasers. The corresponding index of refraction associated with the group velocity of the probe laser can be controlled at both transparency windows by the coupling fields. The propagation of the probe field can be switched from superluminal near the resonance to subluminal on resonance within the single transparency window when two coupling lasers are on resonance. This provides a potential application in quantum information processing. We propose an atomic $^{87}Rb$ system for experimental observation.