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arXiv · 2501.01188

Nearsightedness in Materials with Indirect Band Gaps

Huajie Chen·Juerong Feng·Christoph Ortner·Jack Thomas
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Abstract

We investigate the nearsightedness property in the linear tight binding model at zero Fermi-temperature. We focus on the decay property of the density matrix for materials with indirect band gaps. By representing the density matrix in reciprocal space, we establish a qualitatively sharp estimate for the exponential decay rate in homogeneous systems, possibly with localized perturbations. This work refines the estimates presented in (Ortner, Thomas & Chen, 2020) for systems with small band gaps.

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Huajie Chen, Juerong Feng, Christoph Ortner, Jack Thomas. 2025-01-02. Nearsightedness in Materials with Indirect Band Gaps. https://arxiv.org/abs/2501.01188

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