Tailoring the Third-Order Nonlinear Optical Property of a Hybrid Semiconductor Quantum Dot-Metal Nanoparticle: From Saturable to Fano-Enhanced Absorption
Tailoring the Third-Order Nonlinear Optical Property of a Hybrid Semiconductor Quantum Dot-Metal Nanoparticle: From Saturable to Fano-Enhanced Absorption
复制标题
定制混合半导体量子点金属纳米粒子的三阶非线性光学特性：从可饱和到法诺增强吸收
DOI：
10.1021/acs.jpclett.9b02627
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发表时间：
2019-12-19
影响因子：
5.7
通讯作者：
Zhang, Xinhui
中科院分区：
文献类型：
--
作者：
Liu, Xiaona;Kongsuwan, Nuttawut;Zhang, Xinhui
半导体-金属混合纳米结构由于其潜在的光电应用而呈现出一类奇特的非线性光学材料。然而，迄今为止，大多数研究都关注它们的总光学响应，而不是单个非线性阶次的贡献。在这封信中，我们提出了混合胶体半导体量子点（SQD）-金属纳米粒子（MNP）系统的三阶非线性光学吸收的理论研究。我们开发了一种基于非线性密度矩阵方程的新型分析处理方法，并推导了光学磁化率的封闭式表达式。我们的。研究确定了控制系统从可饱和吸收器到法诺增强吸收器的光学转变的参数空间。我们将这种转变归因于 SQD 等离激元介导的自相互作用。该研究结果为基于SQD-MNP混合结构的功能纳米光子器件的优化设计提供了有价值的指导。
Semiconductor-metal hybrid nanostructures present an exotic class of nonlinear optical materials due to their potential optoelectronic applications. However, most studies to date focus on their total optical responses instead of contributions from individual nonlinear orders. In this Letter, we present a theoretical study on the third-order nonlinear optical absorption of a hybrid colloidal semiconductor quantum dot (SQD)-metal nanoparticle (MNP) system. We develop a novel analytic treatment based on the nonlinear density matrix equation and derive a closed-form expression for the optical susceptibility. Our. study identifies the parameter space that governs the system's optical transition from being a saturable absorber to a Fano-enhanced absorber. We attribute this transition to the plasmon-mediated self-interaction of the SQD. The findings provide a valuable guideline for optimized designs of functional nanophotonic devices based on SQD-MNP hybrid structures.