Quantum mechanics

Anisotropy

Oxide

Metallurgy

Materials science

Physics

Optics

Superconductivity

Superconducting coherence length

Condensed matter physics

Crystallography

Transition temperature

Chemistry

Coherence length

Physical Review Letters

We report on the observation of a ${T}_{c}\ensuremath{\sim}0.9\text{ }\text{ }\mathrm{K}$ superconductivity at the interface between ${\mathrm{LaAlO}}_{3}$ film and the $5d$ transition metal oxide ${\mathrm{KTaO}}_{3}(110)$ single crystal. The interface shows a large anisotropy of the upper critical field, and its superconducting transition is consistent with a Berezinskii-Kosterlitz-Thouless transition. Both facts suggest that the superconductivity is two-dimensional (2D) in nature. The carrier density measured at 5 K is $\ensuremath{\sim}7\ifmmode\times\else\texttimes\fi{}{10}^{13}\text{ }\text{ }{\mathrm{cm}}^{\ensuremath{-}2}$. The superconducting layer thickness and coherence length are estimated to be $\ensuremath{\sim}8$ and $\ensuremath{\sim}30\text{ }\text{ }\mathrm{nm}$, respectively. Our result provides a new platform for the study of 2D superconductivity at oxide interfaces.

Two-Dimensional Superconductivity at the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mrow><mml:mi>LaAlO</mml:mi></mml:mrow><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msub><mml:mo>/</mml:mo><mml:msub><mml:mrow><mml:mi>KTaO</mml:mi></mml:mrow><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msub><mml:mo stretchy="false">(</mml:mo><mml:mn>110</mml:mn><mml:mo stretchy="false">)</mml:mo></mml:math> Heterointerface

Two-Dimensional Superconductivity at the LaAlO3/KTaO3(110) Heterointerface