Electrical transport properties and confinement potential analysis of buried AlGaAs/GaAs quantum wires

Abstract

Buried wires with lateral potential barriers provided by AlGaAs/GaAs heterointerfaces have been fabricated by wet etching and metalorganic chemical vapor deposition regrowth. Burying the wire was proven to enhance the electrical transport properties; for example, it decreased the critical width and increased the subband energy separation. Two-dimensional simulation using the Poisson equation was performed to obtain the potential profile of both as-etched and buried wires. The quantum energy levels corresponding to the lateral confinement were calculated for the obtained potential profiles. The calculated energy separations agreed well with the experimental ones and the subband energy separation of the buried wire was larger than that of the as-etched wire for the same effective width. These results show that burying wire is effective for creating strong lateral confinement.