Self-energy of strongly interacting fermions in medium: A holographic approach

Abstract

We consider the self-energy of strongly interacting fermions in the medium using gauge/gravity duality of D4/D8 system. We study the mass generation of the thermal and/or dense medium and the collective excitation called plasmino, by considering the spectral function of fermion and its dispersion relation. Our results are very different from those of the hard thermal loop method: for zero density, there is no thermal mass or plasmino in any phase. Plasmino in the deconfined phase is not allowed in D4/D8 setup. In the confined phase, there is a plasmino mode only for a window of density.