Observation of large Stark shift in Ge<i>x</i>Si1−<i>x</i>/Si multiple quantum wells

Abstract

Large quantum-confined Stark shift is observed in a type II GeSi/Si multiple quantum well structure for the first time. In this experiment, we have employed the photocurrent measurement using reverse biased p-i-n diodes with multiple quantum wells in the i-region. The photocurrent as a function of bias is carried out at 77 and 300 K. The results show large red shift of the absorption edge which is about 0.75 meV kV−1 cm. This suggests the application of GeSi/Si type II structure for nonlinear electro-optics devices near the 1.3 μm range.