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

本计画旨在从理论上研究强耦合于光腔的单一及多重半导体量子点中光激发（激子）的相干动力学。特别是，相干耦合和控制远程量子点通过光学谐振器在光路将被调查。这样的量子点扮演着隔离量子比特的角色，它们的受控耦合对于量子技术应用至关重要。该项目的具体目标包括计算：（一）嵌入光学谐振腔的单个和多个量子点的线性和非线性光学响应。您将考虑相干响应（如线性，四波和六波混合偏振）和非相干响应（如光致发光）。(ii)与相同腔或不同腔相互作用的远程QD的相干耦合，以及经由腔参数控制QD之间的这种耦合。(iii)用多体理论的方法，如图解法，研究了激子-声子-光子耦合系统的全相干动力学，以及阐明声学声子在量子点相干耦合和光学腔体内珀塞尔增强其辐射衰减中的作用。该项目嵌入在卡迪夫物理和天文学院的一个更大的EPSRC资助的研究活动中，并将受益于与一个实验研究小组致力于通过腔体控制量子点的远程相干耦合。将理论与测量的光学数据进行比较，将理解相干耦合的基本机制，并提取测量系统的重要参数，用于嵌入复杂量子电路中的QD系统的预测建模。《自然》集团期刊上最近的研究出版物证实了其科学卓越性。

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.