Traveling-wave photodetector with asymmetrically heterostructured intrinsic region

Abstract

Bandwidth limitation by carrier transit time was analyzed mathematically when traveling-wave photodetector's intrinsic region consists of heterostructure. Because of the smaller hole's velocity than electron's, the hole transit length is crucial for determining the large bandwidth. In order to compensate the small transit velocity of hole, we propose that the intrinsic region should be designed asymmetrically. In this study we found that appropriate asymmetric structure enhanced bandwidth by about 100% of symmetric structure and proved experimentally the effect of asymmetric intrinsic region.