光子晶体点缺陷在入射光激励下的响应特性研究

Study on the Response of Photonic Crystal Point Defects to the Excitation of Incident Light

研究了光子晶体点缺陷在入射光激励下的响应特性,通过理论分析可以获得点缺陷的透射谱.分析发现,非线性点缺陷的缺陷模在入射光的激励下发生动态移动,且满足两个特征:首先,入射光功率强度越大,缺陷模移动幅度越大.其次,整个缺陷模的透射率随着功率强度的增大而降低.采用泵浦-探测技术的数值模拟方法可获得非线性点缺陷的动态特征.泵浦光和探测光可以选择不同频率以使缺陷模的特征比较清晰.所得现象与理论分析结果一致.该结论为该类光子晶体的应用提供理论依据.

The response of nonlinear photonic crystal defects to the excitation of incident light is investigated. The transmission spectrum of point defects can be obtained by theoretical analysis,which is referred to as defect modes.The analysis found that the defect mode of a defect with Kerr nonlinearity will be shifted instantaneously once the defect is excited by an incident light.There are two features.First,the shift of the defect mode is increased with the increase of light intensity.Second,the transmitted intensity of the defect mode is reduced with the increase in light intensity.The dynamics of point defects can be obtained by use of numerical simulations in a pump-probe technique.The pump and probe waves are set at different frequencies,ensuring the clear identification of the dynamics of the point defect.The results are consistent with the theoretic analyses.The result provides a theoretical base of the application of these sorts of photonic crystals.