Photoinduced Screening Breakdown Mediated by Plasmon Excitations and Potential Instabilities in the System

Abstract

In this work, we estimate the effect of photoinduced screening breakdown of the Coulomb potential mediated by plasmons. In contrast to previous studies, we consider the contribution from the divergence of renormalized inverse electron permittivity, which enhances Coulomb interaction at longer ranges. Our work reveals that the Coulomb potential acquires oscillating terms, which for the charged plane case could lead to a spatial heterostructure. In the resonant case ($\omega_p = \Omega$), photoinduced Coulomb interaction becomes attractive for small values of momenta. This Coulomb interaction renormalization could potentially lead to instabilities in the electron system, such as superconductivity and/or charge density waves. We found possible divergence of the electron coupling constant and discuss herein a potential new mechanism of superconductivity based on electron-electron interaction renormalization via the plasmon oscillating electric field. We also briefly discuss possible photoinduced $\epsilon$ near zero conditions.