Quantum well avalanche multiplication initiated by 10 μm intersubband absorption and photoexcited tunneling

Abstract

We have achieved avalanche gain at a wavelength of 10.3 μm in AlxGa1−xAs/GaAs quantum well superlattices. The photoelectrons are generated by resonant intersubband absorption and tunneling, and then avalanche via hot-electron impact ionization of carriers out of the quantum wells. Good agreement is obtained between a theoretical calculation of this process and our experiments.