Two-dimensional superconductivity at (110) LaAlO3/SrTiO3 interfaces

TL;DR

This paper reports the discovery of two-dimensional superconductivity at (110) LaAlO3/SrTiO3 interfaces, with a transition temperature of 184 mK, confirmed by transport measurements and Berezinskii-Kosterlitz-Thouless analysis, showing features similar to (001) interfaces.

Contribution

It demonstrates for the first time two-dimensional superconductivity at (110) LAO/STO interfaces, expanding understanding of quantum phenomena in these heterostructures.

Findings

Superconducting transition temperature of 184 mK.

Superconductive thickness estimated at about 18 nm.

Features comparable to (001) LAO/STO interfaces.

Abstract

Novel low dimensional quantum phenomena are expected at (110) LaAlO3/SrTiO3 (LAO/STO) interfaces after the quasi two dimensional electron gas similar to that of (001) LAO/STO interfaces was found [G. Herranz et al., Sci. Rep. 2, 758 (2012) and A. Annadi et al., Nat. Commun. 4, 1838 (2013)]. Here, two dimensional superconductivity of (110) LAO/STO samples with a superconducting transition temperature of 184 mK is demonstrated based on systematical transport measurements. The two dimensional characteristic of the superconductivity is confirmed by analyzing the Berezinskii-Kosterlitz-Thouless transition. The estimated superconductive thickness is about 18 nm. These features of superconductivity of (110) LAO/STO interfaces are comparable to those of (001) LAO/STO interfaces. This discovery may inspire a new round of upsurge on study of LAO/STO interfaces.