SiC Detectors for Sub-GeV Dark Matter

TL;DR

This paper explores silicon carbide (SiC) as a versatile and tunable material for direct detection of sub-GeV dark matter, capable of sensing various dark matter interactions down to very low energies.

Contribution

It introduces SiC as a new detector material with unique properties, expanding the range of detectable dark matter masses and interaction types compared to existing materials.

Findings

SiC can detect dark matter down to 10 keV mass via electron, nuclear, and phonon excitations.

SiC can also detect dark matter absorption processes down to 10 meV.

It offers a tunable sensitivity due to multiple stable polymorphs and has practical advantages over diamond.

Abstract

We propose the use of silicon carbide (SiC) for direct detection of sub-GeV dark matter. SiC has properties similar to both silicon and diamond, but has two key advantages: (i) it is a polar semiconductor which allows sensitivity to a broader range of dark matter candidates; and (ii) it exists in many stable polymorphs with varying physical properties, and hence has tunable sensitivity to various dark matter models. We show that SiC is an excellent target to search for electron, nuclear and phonon excitations from scattering of dark matter down to 10 keV in mass, as well as for absorption processes of dark matter down to 10 meV in mass. Combined with its widespread use as an alternative to silicon in other detector technologies and its availability compared to diamond, our results demonstrate that SiC holds much promise as a novel dark matter detector.