Giant conductivity switching of LaAlO3/SrTiO3 heterointerfaces governed by surface protonation.

ABSTRACT: Complex-oxide interfaces host a diversity of phenomena not present in traditional semiconductor heterostructures. Despite intense interest, many basic questions remain about the mechanisms that give rise to interfacial conductivity and the role of surface chemistry in dictating these properties. Here we demonstrate a fully reversible >4 order of magnitude conductance change at LaAlO3/SrTiO3 (LAO/STO) interfaces, regulated by LAO surface protonation. Nominally conductive interfaces are rendered insulating by solvent immersion, which deprotonates the hydroxylated LAO surface; interface conductivity is restored by exposure to light, which induces reprotonation via photocatalytic oxidation of adsorbed water. The proposed mechanisms are supported by a coordinated series of electrical measuremen

SUBMITTER: Brown KA 

PROVIDER: S-EPMC4749969 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature