提出了光学-力学相干耦合的概念,采用非线性光学的耦合波理论,建立了高功率激光辐照下透明光学材料中相干声波的产生、演化的动力学模型.探讨了在泵浦激光场和Stokes激光场共同作用下受激布里渊过程对光学材料破坏的可能性,计算了稳态情况下激光场在材料内部激发出的应力幅度,结合弹性力学,建立了透明光学材料的相干破坏阈值理论,研究了破坏阈值与Stokes光强的关系,发现在稳态下破坏阈值对Stokes光强并不敏感.分析了在实际情况下一些因素对材料破坏的影响.

The concept of coherent coupling of optics and mechanics is presented here and its mechanism is analyzed. The coupled wave theory of nonlinear optics is adopted to establish nonlinear dynamics model describing generation and evolution of coherent acoustic wave in optical materials. The stress induced by SBS process is calculated in steady state case and the damage threshold theory for transparent materials is presented to study the dependence of damage threshold on Stokes laser fluence.The research shows that the SBS induced stress would cause material breakdown which most probably happens in the entrance surface of pump laser, and the Stokes laser does not play an important role in the damage thresholds in steady case. Finally, the future work is outlined to promote the study on coherent coupling of optics and mechanics.