Tunable Superconducting Order at the (111) LaAlO$_{\mathrm{3}}$/SrTiO$_{\mathrm{3}}$ Interface*

Interfacial superconductivity in (001) LaAlO$_{\mathrm{3}}$/SrTiO$_{\mathrm{3}}$ (LAO/STO) heterostructures is well studied and is known to be tunable, coexists with ferromagnetism, and exhibits a superconductor-to-insulator transition. On the other hand, the (111) orientation of LAO/STO has only been shown relatively recently to play host to a 2DEG, and is particularly interesting due to its complex Fermi surface, and potential topological characteristics. We have previously reported detailed transport studies on (111) LAO/STO devices, conducted at 4.4K, which are strikingly different from results in the (001) heterostructures. In particular, these heterostructures exhibit strong anisotropy along two orthogonal, in plane crystal directions as a function of electrostatic back-gate voltage.$^{\mathrm{1}}$ Here we report on the superconducting properties of PLD grown (111) LAO/STO heterostructures at mK temperatures. Specifically, we measure the low frequency transport properties along both two orthogonal, in-plane, crystal directions in response to an applied electrostatic back gate potential as well as post growth surface treatments. 1) S. Davis, V. Chandrasekhar, Z. Huang, K. Han, Ariando, T. Venkatesan, \textit{Arxiv, }\textbf{2015 }1603.04538.