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arXiv 1306.5790cond-mat.mes-hallphysics.chem-ph
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无序系统中的相干量子输运I:退相对一维系统输运性质和吸收光谱的影响

Coherent quantum transport in disordered systems I: The influence of dephasing on the transport properties and absorption spectra on one-dimensional systems

Jeremy M. Moix, Michael Khasin, Jianshu Cao

摘要:

研究了在Haken-Strobl-Reineker模型描述的热涨落存在下,静态无序一维系统中激子的输运.在短时间内,观察到非扩散行为,其特征在于安德森局域系统中的自由粒子动力学。在较长的时间尺度上,环境诱导的退相足以克服由无序引起的安德森局域化,并允许发生总是被视为扩散的传输。在弱和强退相量子主方程的限制制度的开发,和它们各自的标度关系意味着存在的扩散常数作为一个函数的退相率,这是数值确认的最大值。在弱退相制度,它表明,扩散常数是成正比的本地化长度的平方,从而导致显着增强的传输速率超过经典的预测。最后讨论了噪声和无序对吸收谱的影响及其与输运性质的关系。

英文摘要:

Excitonic transport in static disordered one dimensional systems is studied in the presence of thermal fluctuations that are described by the Haken-Strobl-Reineker model. For short times, non-diffusive behavior is observed that can be characterized as the free-particle dynamics in the Anderson localized system. Over longer time scales, the environment-induced dephasing is sufficient to overcome the Anderson localization caused by the disorder and allow for transport to occur which is always seen to be diffusive. In the limiting regimes of weak and strong dephasing quantum master equations are developed, and their respective scaling relations imply the existence of a maximum in the diffusion constant as a function of the dephasing rate that is confirmed numerically. In the weak dephasing regime, it is demonstrated that the diffusion constant is proportional to the square of the localization length which leads to a significant enhancement of the transport rate over the classical prediction. Finally, the influence of noise and disorder on the absorption spectrum is presented and its relationship to the transport properties is discussed.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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