Cooperative robustness to static disorder: Superradiance and localization in a nanoscale ring to model light-harvesting systems found in nature

Article

关键词: CONTINUUM SHELL-MODEL;    QUANTUM COHERENCE;    PHOTOSYNTHETIC UNIT;    ENERGY-TRANSFER;    DYNAMICS;    EXCITATION;    TRANSITION;    ABSENCE;   

DOI  :  10.1103/PhysRevB.90.075113

来源: SCIE

【 摘 要 】

We analyze a one-dimensional ring structure composed of many two-level systems, in the limit where only one excitation is present. The two-level systems are coupled to a common environment, where the excitation can be lost, which induces super-and subradiant behavior, an example of cooperative quantum coherent effect. We consider time-independent random fluctuations of the excitation energies. This static disorder, also called inhomogeneous broadening in literature, induces Anderson localization and is able to quench superradiance. We identify two different regimes: (i) weak opening, in which superradiance is quenched at the same critical disorder at which the states of the closed system localize; (ii) strong opening, with a critical disorder strength proportional to both the system size and the degree of opening, displaying robustness of cooperativity to disorder. Relevance to photosynthetic complexes is discussed.

【 授权许可】

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