Photoluminescence measurements in Be-delta-doped back-gate induced quantum well

TL;DR

This study investigates how photoluminescence spectra in a Be-delta-doped GaAs/AlGaAs quantum well vary with electron density controlled by a back gate, revealing linear PL increase and exciton quenching.

Contribution

It presents the first detailed PL measurements of a back-gate induced 2D electron system in Be-delta-doped quantum wells, showing how PL features change with electron density.

Findings

PL spectrum around 1.49 eV increases linearly with back gate voltage.

PL from exciton bound to neutral donors disappears at low electron density.

Electron density can be tuned from 10^9 to 2.5×10^{11} cm^{-2}.

Abstract

The photoluminescence (PL) spectra of a two-dimensional electron system induced in a Be-delta-doped GaAs/AlGaAs quantum well (QW) with a back gate are measured. The electron density is controlled from 1 X 10^{9} cm^{-2} to 2.5 X 10^{11} cm^{-2} by changing the back gate voltage. There is a linear increase in the acceptor PL spectrum around 1.49 eV with an increase in the back gate voltage and the PL disappears from the exciton bound to neutral donors (D^{0}X) around 1.51 eV at 1.2 X 10^{10} cm^{-2}.