Photoluminescence and photoluminescence excitation spectroscopy of GaAs/Al0.3Ga0.7As multiple quantum wells at low temperature using a lamp with monochromator

Abstract

This study aims to use a xenon (Xe) arc lamp coupled with a monochromator to make a photoluminescence excitation (PLE) spectroscopy setup for device characterization. PLE spectroscopy allows us to access higher-order transitions and longitudinal optical (LO) phonon deexcitation dynamics in a multiple quantum well (MQW). The devised PLE setup was used to perform PL and PLE measurements at 13 K on well-characterized GaAs/Al_0.3Ga_0.7As MQW samples of nominal well widths 50 Å, 90 Å, and 120 Å. The PL spectra obtained were compared to the PL spectra from a laser to check the viability of the setup. The peaks in the PLE spectra were analyzed and identified based on calculated values using a finite square potential well approximation. The PL peaks from the lamp showed good agreement with the PL peaks from the laser, indicating the lamp as a good alternative light source for PL measurements. The PLE spectra showed peaks corresponding to the transition energies and GaAs LO phonon emission of the samples that are near the expected values. The setup proves to be viable on PLE measurements.