Note: On the memory kernel and the reduced system propagator

Lyran Kidon; Haobin Wang; Michael Thoss; Eran Rabani

doi:10.1063/1.5047446

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arXiv · 1807.07206

Note: On the memory kernel and the reduced system propagator

Lyran Kidon·Haobin Wang·Michael Thoss·Eran Rabani

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Abstract

We relate the memory kernel in the Nakajima-Zwanzig-Mori time-convolution approach to the reduced system propagator which is often used to obtain the kernel in the Tokuyama-Mori time-convolutionless approach. The connection provides a robust and simple formalism to compute the memory kernel for a generalized system-bath model circumventing the need to compute high order system-bath observables. We illustrate this for a model system with electron-electron and electron-phonon couplings, driven away from equilibrium.

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Lyran Kidon, Haobin Wang, Michael Thoss, Eran Rabani. 2018-07-19. Note: On the memory kernel and the reduced system propagator. https://doi.org/10.1063/1.5047446

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