Orientational tuning of the 2D-superconductivity in LaAlO3/SrTiO3 interfaces

Abstract

The discovery of a two-dimensional (2D) electron gas at the (110)-oriented LaAlO3/SrTiO3 in- terface provided us with the opportunity to probe the effect of crystallographic orientation and the ensuing electronic reconstructions on interface properties beyond the conventional (001)-orientation. At temperatures below 200 mK, we have measured 2D superconductivity with a spatial extension significantly larger (d approx. 24 - 30 nm) than previously reported for (001)-oriented LaAlO3/SrTiO3 interfaces (d approx. 10 nm). The more extended superconductivity brings about the absence of violation of the Pauli paramagnetic limit for the upper critical fields, signaling the distinctive nature of the electronic structure of the (110)-oriented interface with respect to their (001)-counterparts