Two-dimensional superconductivity and anisotropic transport at KTaO3 (111) interfaces

A superconducting interface

Interfaces between offers can harbor quantum states that belong to neither of the offers. A conventional instance is the superconducting interface between two insulating oxides, LaAlO₃ and SrTiO₃, with a considerable temperature of around 200 millikelvin. Liu et al. noticed superconductivity at a diversified interface—fashioned between KTaO₃ as a substrate and an overlayer of both EuO or LaAlO₃—at a critically elevated temperature of about 2 kelvin. Transport measurements displayed anisotropy, which can also contemporary an unfamiliar superconducting issue.

Science, this ache p. 716

Summary

The distinctive digital construction came all the contrivance thru at interfaces between offers can enable unconventional quantum states to emerge. Here we file on the discovery of superconductivity in electron gases fashioned at interfaces between (111)-oriented KTaO₃ and insulating overlayers of both EuO or LaAlO₃. The superconducting transition temperature, as high as 2.2 kelvin, is set one show of magnitude elevated than that of the LaAlO₃/SrTiO₃ machine. Particularly, identical electron gases at KTaO₃ (001) interfaces stay fashioned down to 25 millikelvin. The considerable enviornment and up to the moment-voltage measurements contemporary that the superconductivity is 2-dimensional. In EuO/KTaO₃ (111) samples, a spontaneous in-airplane transport anisotropy is noticed earlier than the onset of superconductivity, suggesting the emergence of a undeniable “stripe”-like share, which is furthermore published approach the considerable enviornment.