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تسجيل مستخدم جديدLocalization enhanced dissipation in the generalized Aubry-Andr{e}-Harper model coupled to Ohmic baths
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In this work, the non-Markovian dynamics of excitation in the generalized Aubry-Andr{e}-Harper model coupled with an Ohmic-type environment is discussed in detail by evaluating the survival probability and inverse participation ratio of the state of system. Contrary to the common belief that localization will preserve the information of the initial state in the system against dissipation into the environment, this study found that strong localization can enhance the dissipation of quantum information. Through a thorough examination, we show that the non-Markovianity induced by the memory effect of the environment was responsible for this behavior. Under this circumstance, the exchange of energy between the system and its environment may lead to interference in the reduced energy levels of the system, that are also responsible for the stability of the system. In term of strong localization, the difference between reduced energy levels will become large, to the degree that the environment cannot feed back enough energy into the system. As a result, the initial-state information will eventually dissipate. This explanation was verified herein by an increase of the coupling strength between the system and its environment, which greatly reduced the decaying of quantum information.
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