Six-Fold Degenerate Dark States in a Four-Level Atomic System

与拉曼回声上的所有开车的地，一种三脚架类型原子 systemquickly 从有损耗的激动的水平演变为黑暗州的 decoupled。黑暗在 acomplicated 在地 Rabi 频率，自发的腐烂率，和起始的原子人口上 dependsstrongly 说方法。分析结果表明它是有它的 threecomponents 的一个六倍的退化黑暗状态由于人口再分配 fromspontaneous 排放协调地并且无条理地迭加。

With all driving fields on Raman resonance, a tripod-type atomic system quickly evolves into a dark state decoupled from the lossy excited level. The dark state depends strongly on field Rabi frequencies, spontaneous decay rates, and the initial atomic population in a complicated way. Analytical results reveal that it is a sixfold degenerate dark state with its three components superposed both coherently and incoherently due to population redistribution from spontaneous emission.