Quantum oscillations and subband properties of the two-dimensional electron gas at the LaAlO3/SrTiO3 interface

Abstract

We have performed high field magnetotransport measurements to investigate the interface electron gas in a high mobility SrTiO3/SrCuO2/LaAlO3/SrTiO3 heterostructure. Shubnikov-de Haas oscillations reveal several 2D conduction subbands with carrier effective masses of 0.9me and 2me, quantum mobilities of order 2000 cm2/V s, and band edges only a few millielectronvolts below the Fermi energy. Measurements in tilted magnetic fields confirm the 2D character of the electron gas, and show evidence of inter-subband scattering.