Detection of sub-MeV Dark Matter with Three-Dimensional Dirac Materials

Understand

We propose the use of three-dimensional Dirac materials as targets for direct detection of sub-MeV dark matter.

• Dirac materials are characterized by a linear dispersion for low-energy electronic excitations, with a small band gap of O(meV) if lattice symmetries are broken.
• Dark matter at the keV scale carrying kinetic energy as small as a few meV can scatter and excite an electron across the gap.
• Alternatively, bosonic dark matter as light as a few meV can be absorbed by the electrons in the target.