Nearsightedness in Materials with Indirect Band Gaps
Mathematical Physics
2026-01-28 v2 math.MP
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.
Cite
@article{arxiv.2501.01188,
title = {Nearsightedness in Materials with Indirect Band Gaps},
author = {Huajie Chen and Juerong Feng and Christoph Ortner and Jack Thomas},
journal= {arXiv preprint arXiv:2501.01188},
year = {2026}
}