Energy Band Analysis of MQW Structure Based on Kronig-Penny Model

Abstract

The effects of different potential well depths, well widths and barrier widths on energy band of multiple quantum well (MQW) structures are discussed in detail based on Kronig-Penny model. The results show that if the well and barrier width stay unchanged, the first and second band gaps increase linearly with the well depth. When the well depth is constant, the first and second band gaps increase exponentially with the barrier width in a wide well. However, in narrow well one, the second band gap saturates when the barrier width is wide enough. On condition that the well and barrier have equal width, the first band gap decreases exponentially with well-barrier width while the second gap still shows an exponential increase with the width. The se results are insightful for the design of MQW structure optoelectronic devices.