Electron-hole superfluidity controlled by a periodic potential

Abstract

We propose controlling an electron-hole superfluid in semiconductor coupled quantum wells and double layers of a two-dimensional (2D) material by an external periodic field. This can be created either by the gates periodically located and attached to the quantum wells or double layers of the 2D material or by the moiré pattern of two twisted layers. The dependence of the electron-hole pairing order parameter on the temperature, the charge carrier density, and the gate parameters is obtained by minimization of the mean-field free energy. The second-order phase transition between superfluid and electron-hole plasma, controlled by the external periodic gate field, is analyzed for different parameters.