Exploiting Negative Capacitance for Unconventional Coulomb Engineering

TL;DR

This paper explores how negative capacitance in engineered structures can enable Coulomb interactions to become attractive, potentially leading to new electronic phases like superconductivity in two-dimensional systems.

Contribution

It introduces the concept of using negative capacitance to achieve unconventional Coulomb engineering, expanding the possibilities for manipulating electron interactions.

Findings

Negative capacitance can induce attractive electron interactions.

Engineered environments can stabilize correlated electronic phases.

Parameter regimes for potential superconductivity are outlined.

Abstract

The many-body ground state of a two-dimensional electron system can be tuned by Coulomb engineering through control of the dielectric environment. However, in conventional dielectrics the static permittivity is restricted to positive values, limiting the accessible interaction regimes. Here we argue that the negative capacitance demonstrated in appropriately engineered structures can open new vistas for Coulomb engineering. The associated negative permittivity could transform the natural repulsive interaction of electrons into an attractive one, raising the intriguing possibility of nontrivial ground states, including superconductivity. Using models of two-dimensional electron systems with linear and parabolic dispersion relations coupled to environments with negative capacitance, we estimate the strength and sign of the engineered Coulomb interaction and outline parameter regimes that could stabilize correlated electronic phases.