Eliashberg theory for dynamical screening in bilayer exciton condensation

Abstract

We study the effect of dynamical screening of interactions on the transition temperatures ($T_c$) of exciton condensation in a symmetric bilayer of quadratically dispersing electrons and holes by solving the linearized Eliashberg equations for the anomalous interlayer Green's functions. We find that $T_c$ is finite for the range of density and layer separations studied, decaying exponentially with interlayer separation. $T_c$ is suppressed well below that predicted by a Hartree Fock mean field theory with unscreened Coulomb interaction, but is above the estimates from the statically screened Coulomb interaction. Furthermore, using a diagrammatic framework, we show that the system is always an exciton condensate at zero temperature but $T_c$ is exponentially small for large interlayer separation.

References in corpus (12)

• Evidence of high-temperature exciton condensation in 2D atomic double layers
• Room-Temperature Superfluidity in Graphene Bilayers
• Electron screening and excitonic condensation in double-layer graphene systems
• Evidence for equilibrium excitons and exciton condensation in monolayer WTe2
• Interaction-Enhanced Coherence Between Two-Dimensional Dirac Layers
• Wigner supersolid of excitons in electron-hole bilayers
• Chester supersolid of spatially indirect excitons in double-layer semiconductor heterostructures
• Density fluctuation effects on the exciton condensate in double layer graphene
• Supersolidity in electron-hole bilayers with a large density imbalance
• Josephson-like tunnel resonance and large Coulomb drag in GaAs-based electron-hole bilayers
• Gate-defined Two-dimensional Hole and Electron Systems in an Undoped InSb Quantum Well
• Interaction and coherence in 2D bilayers

Cited by in corpus (3)

• 2D bilayer electron-hole superfluidity with unequal and anisotropic masses
• Longitudinal Josephson effect in systems with pairing of spatially separated electrons and holes
• Unconventional superconductivity mediated by exciton density wave fluctuations