Temperature-dependence of superconducting transition of LaAlO3/SrTiO3 nanowires under uniaxial strain

Oxide interfaces provide new ways to probe superconductivity in lower dimensions. A high-mobility 2D electron gas that can be superconducting at sub-Kelvin temperatures exists at the interface of LaAlO3 and SrTiO3. We can create 1D and 2D nanostructures at the interface of LAO/STO using conductive atomic force microscope (c-AFM) lithography [1]. Here we focus on the effects of uniaxial strain on the transport properties of superconducting quantum wires formed at the LaAlO3/SrTiO3 interface. We find that the superconducting transition temperature is unaffected by uniaxial strain irrespective of the applied strain direction. Although we notice that above the superconducting transition temperature, tension lowers the four-terminal resistance of a quantum nanowire whereas compression increases it. We will discuss the implications of these results in the context of the ferroelastic domain hypothesis.

[1] C. Cen, et al., Nature Materials 7, 298 (2008).