Pressure-induced intra-4f luminescence in GaAs:Er,O

Abstract
In metalorganic chemical vapor deposition grown GaAs:Er,O samples, at ambient pressure, only the ErGa−2O center is excited by above band gap host photoexcitation (host excitation) and shows a sharp infrared luminescence spectra due to intra-4f transitions in the Er3+ ion. It is found, at high pressure, that at least two other Er centers become optically active by host excitation. One of these pressure-induced centers is assigned to a specific Er center having slightly different atomic configuration than the ErGa−2O center by comparing the pressure-induced photoluminescence (PL) spectra with the site-selective PL spectra.