A Projection-based Reduced-order Method for Electron Transport Problems with Long-range Interactions

• URL: http://arxiv.org/abs/2106.03240v1
• Date: Sun, 6 Jun 2021 20:37:09 GMT
• Title: A Projection-based Reduced-order Method for Electron Transport Problems with Long-range Interactions
• Authors: Weiqi Chu and Xiantao Li
• Abstract summary: Long-range interactions play a central role in electron transport. Long-range interactions have to be included in the computation to accurately compute the Coulomb potential. This article presents a reduced-order approach, by deriving an open quantum model for the reduced density-matrix.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Long-range interactions play a central role in electron transport. At the same time, they present a challenge for direct computer simulations, since sufficiently large portions of the bath have to be included in the computation to accurately compute the Coulomb potential. This article presents a reduced-order approach, by deriving an open quantum model for the reduced density-matrix. To treat the transient dynamics, the problem is placed in a reduced-order framework. The dynamics, described by the Liouville von Neumann equation, is projected to subspaces using a Petrov-Galerkin projection. In order to recover the global electron density profile as a vehicle to compute the Coulomb potential, we propose a domain decomposition approach, where the computational domain also includes segments of the bath that are selected using logarithmic grids. This approach leads to a multi-component self-energy that enters the effective Hamiltonian. We demonstrate the accuracy of the reduced model using a molecular junction built from a Lithium chains.

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