Observation of a Many-Body Edge Singularity in Quantum-Well Luminescence Spectra

Abstract

The observation of a many-body, Fermi-energy edge singularity in the low-temperature photoluminescence spectra of InGaAs-InP quantum wells is reported. Strong enhancement of the photoluminescence intensity towards the electron Fermi energy {E%) is observed, due to multiple electron-hole scattering processes to states above E%. Recombination of electrons in states up to E% is allowed by hole localization. The many-body processes are analogous to the core-hole phenomena in the soft-x-ray emission spectra of metals.

Effects of an electron gas on the negative trion in semiconductor quantum wells

“…Coulomb correlations may eventually manifest themselves in the optical response of the system. This many-body effect is characterized by an enhancement of the spectrum intensity known as the Fermi edge singularity [2]. The situation is quite different in the case of low-carrier densities.…”

Fermi-edge singularities in linear and nonlinear ultrafast spectroscopy

“…where ␣ϭ(1ϩV ) 2 . Expression ͑11͒ will be valid in the case of near-resonance excitation and spectrally narrow pulses, that is, ͉ Ϫ 0 ͉Ӷ⑀ c , and (⌬t) Ϫ1 Ӷ⑀ c ( is the excitation energy͒.…”

“…1 This phenomenon has been observed in continuous-wave spectroscopy in a variety of doped semiconductor heterostructures. 2,3 FES arises as a result of the interplay between two different physical processes: the sudden appearance of a hole potential and the presence of an extra electron at the conduction band. Both effects produce charge-density oscillations involving low-energy electron-hole pairs.…”

Many-Electron Effects in Low-Dimensional Semiconductor Structures

“…The explanation of these effects requires a proper treatment of dynamical self-energy and vertex corrections especially for low-dimensional systems (quantum wells and wires) where exciton binding energy is typically comparable to the Fermi energy. The origin of the Fermi edge singularity is associated with the peculiar overlap of many-electron initial and final state wave functions [2,11], i.e. with Pauli exclusion principle.…”