Carrier lifetime in HgTe/CdTe superlattices grown by photoassisted molecular beam epitaxy

摘要

We report excess carrier lifetimes of several hundred nanoseconds in HgTe/CdTe superlattices grown by photoassisted molecular beam epitaxy. The structures were doped eithernhyphen;type in the low 1015cmminus;3range orphyphen;type in the low 1016cmminus;3range, and were designed for peak response in the longhyphen;wave infrared regime. The measured lifetimes, recorded by the transient photoconductivity technique, approach values calculated for alloys of equivalent bandhyphen;gap energy. They indicate that recombination at the superlattice interfaces has been substantially reduced and underscore the recent progress achieved in superlattice growth technology.