Fermi edge singularity in neutral electron-hole system
arXiv:2209.06026 · doi:10.1038/s41567-023-02096-2
Abstract
In neutral dense electron-hole (e-h) systems at low temperatures, theory predicts Cooper-pair-like excitons at the Fermi energy and a BCS-like exciton condensation. Optical excitation allows creating e-h systems with the densities controlled by the excitation power. However, the intense optical excitations required to achieve high densities cause substantial heating of the e-h system that prevents the realization of dense and cold e-h systems in conventional semiconductors. In this work, we study e-h systems created by optical excitation in separated electron and hole layers. The layer separation increases the e-h recombination time and, in turn, the density for a given optical excitation by orders of magnitude and, as a result, enables the realization of the dense and cold e-h system. We found a strong enhancement of photoluminescence intensity at the Fermi energy of the neutral dense ultracold e-h system that evidences the emergence of excitonic Fermi edge singularity due to the Cooper-pair-like excitons at the Fermi energy.
References in corpus (34)
- Vortices and Superfluidity in a Strongly Interacting Fermi Gas
- Bose-Einstein Condensation of Excitons in Bilayer Electron Systems
- High-temperature superfluidity with indirect excitons in van der Waals heterostructures
- Signatures of exciton condensation in a transition metal dichalcogenide
- Spontaneous Coherence in a Cold Exciton Gas
- Exciton condensate in semiconductor quantum well structures.
- Excitonic superfluid phase in Double Bilayer Graphene
- Quantum Hall Drag of Exciton Superfluid in Graphene
- Gate-Tuned Spontaneous Exciton Insulator in Double-Quantum Wells
- Evidence for a Monolayer Excitonic Insulator
- Excitonic condensation in a symmetric electron-hole bilayer
- Evidence for equilibrium excitons and exciton condensation in monolayer WTe2
- Strongly enhanced tunneling at total charge neutrality in double bilayer graphene-WSe heterostructures
- Long-Distance Diffusion of Excitons in Double Quantum Well Structures
- Direct and indirect excitons in semiconductor coupled quantum wells in an applied electric field
- Correlated interlayer exciton insulator in double layers of monolayer WSe2 and moiré WS2/WSe2
- Drift mobility of long-living excitons in coupled GaAs quantum wells
- Exciton-exciton interaction in quantum wells. Optical properties and energy and spin relaxation
- Evidence for a Bose-Einstein condensate of excitons
- Crossover between Strongly-coupled and Weakly-coupled Exciton Superfluids
- Direct observation of excitonic instability in Ta2NiSe5
- Exciton Liquid in Coupled Quantum Wells
- Excitons and biexcitons in symmetric electron-hole bilayers
- Localization and interaction of indirect excitons in GaAs coupled quantum wells
- A dark incompressible dipolar liquid of excitons
- Evidence of ideal excitonic insulator in bulk MoS2 under pressure
- Second order Josephson effect in excitonic insulators
- Phase diagram of bilayer electron-hole plasmas
- Interference dislocations in condensate of indirect excitons
- Transport of dipolar excitons in (Al,Ga)N/GaN quantum wells
- Effect of spatial resolution on the estimates of the coherence length of excitons in quantum wells
- Coherent transport in homojunction between excitonic insulator and semimetal
- Attractive and repulsive dipolar interaction in bilayers of indirect excitons
- Fermi edge singularity in neutral electron-hole system