Quantum signature of exciton condensation

TL;DR

This paper proposes a universal quantum signature to identify and quantify exciton condensation in molecular systems, demonstrated through calculations on graphene and organic molecules, revealing potential for smaller-scale applications.

Contribution

It introduces a method using two-electron reduced density matrices to detect exciton condensation, extending the concept to molecular systems beyond graphene.

Findings

Eigenvalues indicate exciton condensation in pentacene and hexacene EDLs

Potential for exciton condensation in smaller molecular EDLs

Universal quantum signature applicable across different systems

Abstract

Exciton condensation, a Bose-Einstein-like condensation of excitons, was recently reported in an electronic double layer (EDL) of graphene. We show that a universal quantum signature for exciton condensation can be used to both identity and quantify exciton condensation in molecular systems from direct calculations of the two-electron reduced density matrix. Computed large eigenvalues in the particle-hole reduced-density matrices of pentacene and hexacene EDLs reveal the beginnings of condensation, suggesting the potential for exciton condensation in smaller scale molecular EDLs.