离子晶格非简谐振动引起的光学非线性与增强吸收型光双稳

处理了光场（电磁场）与离子晶体的非简谐性振动之间的相互作用问题。导出了用简正坐标即声子模式所表达的非线性晶格动力学和非线性宏观极化。在旋转波近似下，得到在入射光驱动下光子－声子耦合体系的总的相干性哈密顿算符。通过相应的静态方程证明该耦合系统会出现增强吸收型光学双稳性，这也就证明了光场与各种玻色子型固体元激发，如光频支声子和半导体中激子的非线性耦合可以作为增强吸收型光双稳的机制。

Optical Nonlinearities Induced by Anharmonic Vibration of Ionic Lattice and Increasing Absorption Optical Bistability

This paper deals with the intracavity interaction of lightfield with anharmonic lattice vibration of ionic crystal. The nonlinear lattice dynamics and an expression of nonlinear macroscopic polarization are derived in terms of optic phonon modes. Under rotating wave approximation, the total coherent Hamiltonian of photon-phonon coupling system driven by incident field is introduced. By the corresponding equations of steady state, the increasing absorption optical bistability (IAOB), as a nonlinear effect, is demonstrated. The results show that the nonlinear interaction of light field with various elementary excitations of boson type, such as phonon and exciton, may be served as a mechanism for IAOB.