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arXiv · 2412.17436

Dynamical quantum typicality: Simple method for investigating transport properties applied to the Holstein model

Petar Mitrić
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Abstract

We investigate the transport properties of the Holstein model using the numerically exact quantum typicality (QT) approach. Roughly speaking, QT exploits the fact that even a single, randomly chosen pure state can effectively represent the full statistical ensemble in a high-dimensional Hilbert space. This allows us to compute frequency-dependent mobilities, representative of the thermodynamic limit, that are well-converged with respect to all numerical parameters. Our results are compared against other numerically exact methods, and used to analyze the contribution of vertex corrections to frequency-dependent mobility. The promising accuracy and efficiency of the QT approach suggest its applicability to a broader class of Hamiltonians.

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Petar Mitrić. 2024-12-23. Dynamical quantum typicality: Simple method for investigating transport properties applied to the Holstein model. https://doi.org/10.1103/physrevb.111.195140

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