One-Dimensional Nature of Superconductivity at the LaAlO3/SrTiO3 Interface

Abstract

We examine superconductivity in LaAlO_{3}/SrTiO_{3} channels with widths that transition from the 1D to the 2D regime. The superconducting critical current is independent of the channel width and increases approximately linearly with the number of parallel channels. Signatures of electron pairing outside of the superconducting regime are also found to be independent of the channel width. Collectively, these results indicate that superconductivity exists at the boundary of these channels and is absent within the interior region of the channels. The intrinsic 1D nature of superconductivity at the LaAlO_{3}/SrTiO_{3} interface imposes strong physical constraints on possible electron pairing mechanisms.

Inhomogeneous superconductivity and quasilinear magnetoresistance at amorphous LaTiO3/SrTiO3 interfaces

“…This is the more important since it is often assumed that amorphous layers per se need not yield significantly different physics than crystalline layers. Previously, inhomogeneities in the conductance have been shown to arise from ferroelastic domains [56][57][58][59][60], which strongly affect superconducting properties [57,61]. At the same time, as was mentioned, the quasilinear MR in our samples is much higher than in the crystalline LAO/STO system, indicating an additional significant source of inhomogeneities.…”

Light Bipolarons Stabilized by Peierls Electron-Phonon Coupling

“…Recent work claims a record T c for superconductivity in doped organic p-terphenyl molecules [53,54], where the Peierls coupling is important, and attributes it to a possible bipolaronic mechanism [53]. Similarly, our work may be relevant to understanding electron-phonon driven superconductivity in SrTiO 3 [55], especially given its recently uncovered one-dimensional nature [56], in magic-angle graphene [57], and layered MoS 2 [58].…”

Non-universal current flow near the metal-insulator transition in an oxide interface

“…We neglected gate induced domain motion because we did not observe it in the samples studied. Domain boundaries in LAO/STO are expected to host 1D wave guides with enhanced carrier density 29 , 30 . We expect the detailed electronic properties to change the conductivity of the insulating phase.…”