Exciton-phonon-photon dynamics and coherent coupling of quantum dots embedded in photonic cavities

本项目旨在从理论上研究与光子腔强耦合的单个和多个半导体量子点(QD)中光激发(激子)的相干动力学。特别是，将研究通过光路中的光谐振腔对远程量子点的相干耦合和控制。这种量子点扮演着孤立量子比特的角色，它们的受控耦合对于量子技术的应用是至关重要的。该项目的具体目标包括：(I)计算嵌入光学谐振器中的单个和多个量子点的线性和非线性光学响应。您将同时考虑相干响应(例如线性、四波和六波混频偏振)和非相干响应(例如光致发光)。(Ii)远距离量子点与同一腔或不同腔相互作用的相干耦合，并通过腔参数控制量子点之间的这种耦合。(Iii)耦合激子-声子-光子系统的完全相干动力学，使用多体理论的方法，如图解技术，并阐明声学声子在量子点相干耦合和光腔内的Purcell增强辐射衰减中的作用。该项目嵌入在加的夫物理和天文学学院由EPSRC资助的更大的研究活动中，并将受益于与一个实验研究小组的密切合作，该团队致力于通过腔控制量子点的远程相干耦合。通过将理论与测量的光学数据进行比较，将了解相干耦合的基本机制，并将提取被测系统的重要参数，用于复杂量子电路中的QD系统的预测建模。科学上的卓越得到了最近在《自然》杂志上发表的研究论文的证实。

This project aims to study theoretically the coherent dynamics of optical excitations (excitons) in single and multiple semiconductor quantum dots (QDs) strongly coupled to photonic cavities. In particular, coherent coupling and control of remote QDs via optical resonators in optical circuits will be investigated. Such QDs play the role of isolated qubits, and their controlled coupling is of paramount importance for quantum technology applications. Specific aims of the project include the calculation of: (i) Linear and nonlinear optical response of single and multiple QDs embedded in an optical resonator. You will consider both the coherent response (such as linear, four-wave- and six-wave-mixing polarization) and the incoherent response (such as photoluminescence). (ii) Coherent coupling of remote QDs interacting with the same cavity or different cavities, and control of this coupling between QDs via cavity parameters.(iii) Full coherent dynamics of the coupled exciton-phonon-photon system, using methods of many-body theory, such as diagram techniques, and clarifying the role of acoustic phonons in the coherent coupling of QDs and in the Purcell enhancement of their radiative decay inside an optical cavity.The project is embedded in a bigger EPSRC funded research activity at Cardiff School of Physics and Astronomy and will benefit from a close collaboration with an experimental research team working on the controlled long-range coherent coupling of quantum dots via cavities. Comparing theory with measured optical data, fundamental mechanisms of the coherent coupling will be understood and important parameters of the measured systems will be extracted for predictive modelling of QD systems embedded in complex quantum circuits. The scientific excellence is confirmed by recent research publications in Nature group journals.