Temperature Dependence of the Damping of Nonlinear Lattice Resonance in Ionic Crystals

Abstract

A general expression for the $n\mathrm{th}$-order nonlinear complex-susceptibility tensor is derived by use of many-time temperature-dependent Green's functions. The damping constant for nonlinear absorption is obtained from the susceptibility tensor. It is shown that the $n\mathrm{th}$-order nonlinear susceptibility tensor is generated from lower-order Green's functions and that the explicit temperature dependence of the damping constant is not affected by increasing the strength of the applied field. It is found, by observing the frequency dependence of the susceptibility, that the frequency $\ensuremath{\omega}$ of the applied field is converted into $n\mathrm{th}$-harmonic waves of frequency $n\ensuremath{\omega}$.