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Title: Dark Matter Direct Detection in Materials with Spin-Orbit Coupling
Semiconductors with O(meV) band gaps have been shown to be promising targets to search for sub-MeV mass dark matter (DM). In this paper we focus on a class of materials where such narrow band gaps arise naturally as a consequence of spin-orbit coupling (SOC). Specifically, we are interested in computing DM-electron scattering and absorption rates in these materials using state- of-the-art density functional theory (DFT) techniques. To do this, we extend the DM interaction rate calculation to include SOC effects which necessitates a generalization to spin-dependent wave functions. We apply our new formalism to calculate limits for several DM benchmark models using an example ZrTe5 target and show that the inclusion of SOC can substantially alter projected constraints.
Authors:
; ; ; ; ;
Award ID(s):
1750613
Publication Date:
NSF-PAR ID:
10316750
Journal Name:
ArXivorg
ISSN:
2331-8422
Sponsoring Org:
National Science Foundation
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