Dynamical gap from holography in the charged dilaton black hole

TL;DR

This paper investigates how bulk dipole coupling, fermion charge, and dilaton fields influence spectral properties, flat bands, and phase transitions in holographic non-relativistic fermion systems within charged dilatonic black hole backgrounds.

Contribution

It provides new insights into the effects of dipole coupling and dilaton fields on spectral functions and phase transitions in holographic fermion models.

Findings

Flat band presence suppresses Fermi momentum.

Dipole coupling effects are more pronounced with dilaton fields.

A temperature-induced insulator-to-conductor phase transition is observed.

Abstract

We study the holographic non-relativistic fermions in the presence of bulk dipole coupling in charged dilatonic black hole background. We explore the nontrivial effects of the bulk dipole coupling, the fermion charge as well as the dilaton field on the flat band, the Fermi surface and the emergence of the gap by investigating the spectral function of the non-relativistic fermion system. In particular, we find that the presence of the flat band in the non-relativistic case will suppress the Fermi momentum. Besides, we observe that the effect of the dipole coupling in the dilaton gravity is more explicit. Finally, we consider the non-relativistic fermions at nonzero temperature. A phase transition from insulator to a conducting state is observed as the fermion system becomes hotter.