Highly tunable and efficient room-temperature electroluminescence from GaAs doping superlattices

Using a novel technique of making highly selective contacts to GaAs doping superlattices, tunable electroluminescence (EL) is observed at room temperature with peak energies shifted up to 650 meV below the bulk band gap (λ>1.55 μm). The peak efficiency is about 2%. Comparison is made between the tunable EL spectra at different temperatures from 4 to 300 K and between samples with different doping concentration. Good agreement is obtained with theory.