Electrical Reservoirs for Bilayer Excitons

Abstract

The ground state of two-dimensional (2D) electron systems with equal low densities of electrons and holes in nearby layers is an exciton fluid. We show that a reservoir for excitons can be established by contacting the two layers separately and maintaining the chemical potential difference at a value less than the spatially indirect band gap. Equilibration between the exciton fluid and the contacts proceeds via a process involving virtual intermediate states in which an unpaired electron or hole occupies a free carrier state in one of the 2D layers. We derive an approximate relationship between the exciton-contact equilibration rate and the electrical conductances between the contacts and individual 2D layers when the contact chemical potentials align with the free-carrier bands, and explain how electrical measurements can be used to measure thermodynamic properties of the exciton fluid.

Minor revision of v1. Accepted by PRL

References in corpus (7)

• 2D materials and van der Waals heterostructures
• Quantum fluids of light
• Observation of Long-Lived Interlayer Excitons in Monolayer MoSe2-WSe2 Heterostructures
• Exciton-polariton condensates
• High-temperature superfluidity with indirect excitons in van der Waals heterostructures
• Spontaneous Polarisation Build up in a Room Temperature Polariton Laser
• Indirect excitons in van der Waals heterostructures at room temperature

Cited by in corpus (16)

• Evidence of high-temperature exciton condensation in 2D atomic double layers
• Strongly correlated excitonic insulator in atomic double layers
• Electrically Controlled Two-Dimensional Electron-Hole Fluids
• Long-lived Topological Flatband Excitons in Semiconductor Moiré Heterostructures: a Bosonic Kane-Mele Model Platform
• Keldysh field theory of dynamical exciton condensation transitions in nonequilibrium electron-hole bilayers
• Dynamical exciton condensates in biased electron-hole bilayers
• Josephson-like tunnel resonance and large Coulomb drag in GaAs-based electron-hole bilayers
• Electrical Breakdown of Excitonic Insulator
• Josephson effect as signature of electron-hole superfluidity in bilayers of van der Waals heterostructures
• Interlayer excitonic insulator in two-dimensional double-layer semiconductor junctions: An explicitly solvable model
• Quantum Oscillation in Excitonic Insulating Electron-Hole Bilayer
• Transition to an excitonic insulator from a two-dimensional conventional insulator
• Realization of graphene logics in an exciton-enhanced insulating phase
• Stationary waves in a superfluid gas of electron-hole pairs in bilayers
• Interface engineering of van der Waals heterostructures towards energy-efficient quantum devices operating at high temperatures
• Exciton Superfluidity in 2D Heterostructures from First Principles: The importance of material specific screening