耦合量子点系统非线性光学传感特性的应用研究

Application Research of Nonlinear Optical Sensing Properties in Coupled Quantum Dots System

简要介绍了基于隧穿诱导的固有相干性,耦合量子点系统的非线性光学性质受到干涉效应的影响和变化,及其隧穿测量方面的一些应用。探究了自克尔非线性色散谱对隧穿失谐的灵敏特性,考察了交叉克尔非线性相移对隧穿效应的传感特性,数值模拟结果显示自克尔非线性测量隧穿失谐的精确度可达0.2μeV、系统的交叉相位调制约为0.28rad/μeV;课题组又进一步分析了非线性吸收谱,对隧穿的响应范围为10GHz数量级,并且比较了强弱隧穿情况下,非线性吸收谱对隧穿失谐量的灵敏度的变化,如弱耦合时,吸收谱灵敏度约为3.8μeV;强耦合时,灵敏度大大提高,约为0.4μeV;实现了基于隧穿诱导干涉效应直接提高高阶非线性的方案;提出了利用失谐增强的非线性增益谱表征隧穿变化。

This paper briefly introduced the inherently coherent effects based on tunneling induced interference effects, the nonlinear optical properties of the coupled quantum dots system influenced by the interference effects, and some applications in tunneling measurement. It investigated the sensitivity of self-Kerr nonlinear dispersion to detuning and the sensing properties of cross-Kerr nonlinear phase shift to tunneling effects. The numerical simulation results showed that the detuning accuracy of self-Kerr nonlinear measurements amounted up to 0.2 μeV and the cross-phase modulation was about 0.28 rad/μeV. It further analyzed the nonlinear absorption spectrum and found that the response range was 10 GHz order of magnitudes. It also compared the changes in sensitivity to detuning of the nonlinear absorption spectrum in the cases of weak and strong tunneling. When the coupling was weak, the sensitivity of the absorption spectrum was 3.8 μeV while when the coupling was strong, its sensitivity was greatly improved, approximately 0.4 μeV. The proposed scheme can improve the higher-order nonlinearity based on tunneling induced interference effects and the tunneling changes can be represented by enhanced detuning nonlinear gain spectrum.