Time-resolved study on the impact excitation and quenching processes of the 1.54 μm electroluminescence emission of Er ions in InP

Abstract
Time‐resolved impact excitation and de‐excitation processes of the 1.54 μm electroluminescence (EL) emission of Er3+‐doped InP are investigated. Samples are impact excited by applying electrical pulses and the time response of the EL emission is measured in the temperature range from 77 K to 330 K. The decay of the emission proves almost exponential in all the temperature ranges and shows little thermal quenching with the decay time decreasing from 2 ms at 77 K to only 1 ms at 330 K. This result contrasts with the large thermal quenching and nonexponential characteristics of the photoluminescence (PL) time decay at high temperatures in the same sample, suggesting different excited Er3+ centers between EL and PL. Also measured is the emission rise time as a function of excitation pulse current, giving us the impact cross section of 9×10−16 cm2 for Er3+ ions in InP. The excitation and quenching processes as well as the efficiency of Er emission are analyzed. A model taking into consideration the presence of different Er centers explains the different behaviors in the time responses between EL and PL.