Percolation transport in an AlGaN/GaN heterostructure

Abstract

Magneto-transport in an AlGaN/GaN heterostructure has been studied at 4.2K and it was found that the magneto-resistance is negative at low fields. The negative components disappeared by inserting a thin AlN film between the AlGaN barrier layer and the GaN layer. The negative component is attributed to the presence of alloy disorder at the hetero-interface. It increases linearly followed by saturation, which is characteristic to the percolation transport in random potential. © 2009 IOP Publishing Ltd.