非对称微腔与少数个原子耦合系统的光场调控与全光三极管物理机制

Recently significant breakthroughs have been made in the study of optical manipulation within asymmetrical microcavity. Chaos-assisted broadband momentum transformation in optical microcavities highly enhances light-mater interaction. Here, we present a proposal of controlling strong light with weak light and all-optical transistor in the coupling system containing few two-/three- level atoms and a symmetrical microcavity to overcome some defects remaining in present optical transistors, such as dedicated complexity in scheme, strong-pumping induced instability and long responsive time, etc. This project will focus on such few-particles system to uncover the physical mechanism of controlling strong light with weak light by manipulating atomic saturation absorptive nonlinearity and many-photons coupling nonlinearity and their quantum effects. Combined the contributions of optical controlling by asymmetrical cavity and atomic distribution, we will present an all-optical transistor at atomic and photonic level. Atomic controlling strong light with weak light is superior to classical light-controlling-light under strong pumping, and such transistor is also superior to previous setups since high-quality optical resonator and delicate atomic energy structure are not necessary now. Our research will not only push us to the deep physical insight of interaction between single- / multi- photon(s) and single- / multi- atom(s) in theory, but also provide a theoretical direction and implementation scheme to realize such simple-structured all-optical transistor with low operation intensity and potential silicon-based integration. We also discuss some of the hurdles along the road towards practical implementations, and their possible solutions.

近年来非对称微腔光场调控研究取得了重大突破，混沌辅助的微腔耦合机制极大地提高了光与物质的相互作用。为此我们提出在非对称微腔与少数个二能级/三能级原子耦合系统中实现以弱光控制强光和全光三极管，解决当前全光三极管中结构庞大复杂、性能不稳定等问题。本项目将研究该少粒子系统中原子吸收饱和非线性与多光子耦合非线性及其量子效应调控方法，结合非对称微腔及原子排布对光场的调控，探究在原子系统中以弱光控制强光的物理机制，进而设计原子尺度、光子水平的全光三极管。原子尺度的以弱光控制强光和全光三极管优于宏观经典系统中的以强光控制弱光，也优于现有非经典系统的全光三极管，弱化了对高品质微腔和复杂能级结构等苛刻要求。该研究不仅在理论上有助于深入理解单光子/多光子与单原子/多原子的相互作用物理过程，而且在应用上将为实现这种结构非常简单、工作光强极低且具有潜在硅基可集成性的全光三极管提供理论指导和实现方案。

本课题研究了非对称微腔或光波导与少数个原子耦合系统中的光场调控和全光三极管物理机制，目的是为实现结构简单易于操控、工作光强低性能稳定的全光量子器件提供理论指导和实现方案。根据研究目标，我们按计划开展了研究工作。我们找到了耦合系统中实现光场调控和非线性调控的结构参数，如微腔及光波导泄漏率、原子自发辐射率、原子耦合强度等。随后将耦合系统设置成非对称模式，利用空间对称性破缺引起的非线性量子干涉实现了量子调控和全光三极管。我们还与山西大学张天才教授课题组合作，完成了利用非对称微腔调控原子非线性和光学双稳态的实验工作，验证了对称性破缺对量子场调控理论，理论预测与实验结果完全吻合。此外，我们还在非互易光量子传输和调控方面做了研究，取得了丰硕的成果。