量子点系统中纳米机械振子诱导的光开关

Nanomechanical-Resonator-Assisted Induced Optical Switching in Quantum Dot System

当一个受单色控制场驱动的二能级量子点与单个纳米机械振子相互作用时,作用于此固态量子点系统的弱探测场展现了可调的光开关行为。研究结果表明,当控制场失谐地作用于量子点系统时,改变量子点与纳米机械振子的耦合强度可以有效地实现光开关。同样地,在纳米机械振子的作用下,光开关的行为也可以通过改变控制场的拉比频率来获得。最根本的物理机制是纳米机械振子的耦合建立了量子点的辅助能级,进而控制场诱导了电磁感应透明现象。方案所采取的固态量子系统对宏观量子态有着极其重要的影响,同时这种固态耦合系统的光学开关效应,在光学通信、光子学和非线性光学领域中有着潜在的应用。

Optical switching behavior is presented for the weak probe field applied to the solid-state quantum dot system, which is driven by a strong control field and is coupled with a single nanomechanical resonator. The research results show that it is possible to change the coupling strength of quantum dots with nanomechanical resonator to control optical switching when the driving field is detuned from the quantum dot. It is found that the behavior of optical switching can be obtained via modulating the Rabi frequency of the control field at the presence of the nanomechanical resonator, The responsible physical mechanism is the existence of auxiliary energy levels with the help of the nanomechanical resonator and the occurrence of electromagnetically induced transparency via the control field. The adopted solid-state quantum system plays an extremely important role in the macroscopic quantum state and the optical switching in such a system has the potential applications in optical communications, photonics and nonlinear optics.