Λ型双模激光的朗之万理论

采用朗之万激光理论讨论型双模激光近阈运行的模式耦合特性，双模既可以呈相互抑制和相互支持，又可以呈现一模被抑制另一模被支持以及一模或双模既不被支持又不被抑制。耦合特性不仅取决于双模失谐量，而且与原子三能级初始布居紧密相关。

Langevin Theory of a Λ-Type Two-Mode Laser

Mode coupling of a type two-mode laser operating near above threshold is discussed via Langevin quantum theory. Characteristics of coupling can be have not only mutual decrease and mutual increase but also being increased of one mode and being simultaneously decreased of the other, and both not being increased and not being decreased of either or the two modes. The characteristics depend both on the detunings of the two modes and on the initial populations of three atomic levels.