| Abstract: |
As direct detection experiments expand the search for sub-GeV dark matter and lower their energy thresholds, collective many-body effects can be increasingly important and enhance discovery potential. I will discuss plasmon production in semiconductors from nuclei recoiling against dark matter. Plasmons in semiconductors are the collective longitudinal oscillations of valence electrons, and these modes can be produced at a much higher rate than transverse photons. In addition, because the plasmon can decay into electronic excitations and has characteristic energy given by the plasma frequency, around 16 eV in Si crystals, plasmon production provides a distinctive signature to detect nuclear recoils from sub-GeV dark matter. |
