Two-dimensional electron gas at a molecular beam epitaxial-grown, selectively doped, In0.53Ga0.47As-In0.48Al0.52As interface

Abstract

We report the observation of a high-mobility, two-dimensional electron gas (2DEG) at the interface between a molecular beam epitaxial (MBE)-grown undoped In0.53Ga0.47As layer and a subsequent layer of MBE-grown, Si-doped In0.48Al0.52As . Peak mobilities of ∼92 000 cm2 V−1 s−1 have been observed at 4.2 K. From Hall and Shubnikov-de Haas studies we have found that the 2DEG can be characterized by nch = 6–8×1011 cm−2. In all cases we found two subbands to be occupied at Nch≳4.5×1011 cm−2.