Electric field effect on intersubband oscillator strength of semiconductor quantum disk

Abstract

In this paper, intersubband transition energy and oscillator strength of a semiconductor quantum disk are analytically computed by solving time-independent Schrödinger equation in presence of axial electric field. Results show that transition energy increases with increase of thickness but decreases with increasing radius. The external field alters the potential energy profile of the structure and thus controls the intersubband oscillator strength inside the disk. The oscillator strength between the two lowest subbands decreases with electric field, and increases with thickness of the disk. Results are computed considering first-order band nonparabolicity, and compared with parabolic overestimation. Change in oscillator strength indicates the possibility of wavelength tuning by electric field.