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Dynamical signatures of molecular symmetries in nonequilibrium quantum transport.

ABSTRACT: Symmetries play a crucial role in ubiquitous systems found in Nature. In this work, we propose an elegant approach to detect symmetries by measuring quantum currents. Our detection scheme relies on initiating the system in an anti-symmetric initial condition, with respect to the symmetric sites, and using a probe that acts like a local noise. Depending on the position of the probe the currents exhibit unique signatures such as a quasi-stationary plateau indicating the presence of metastability and multi-exponential decays in case of multiple symmetries. The signatures are sensitive to the characteristics of the probe and vanish completely when the timescale of the coherent system dynamics is much longer than the timescale of the probe. These results are demonstrated using a 4-site model and an archetypal example of the para-benzene ring and are shown to be robust under a weak disorder.

SUBMITTER: Thingna J

PROVIDER: S-EPMC4911572 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Dynamical signatures of molecular symmetries in nonequilibrium quantum transport.

Thingna Juzar J Manzano Daniel D Cao Jianshu J

Scientific reports 20160617

Symmetries play a crucial role in ubiquitous systems found in Nature. In this work, we propose an elegant approach to detect symmetries by measuring quantum currents. Our detection scheme relies on initiating the system in an anti-symmetric initial condition, with respect to the symmetric sites, and using a probe that acts like a local noise. Depending on the position of the probe the currents exhibit unique signatures such as a quasi-stationary plateau indicating the presence of metastability a ...[more]

PMID: 27311717

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