# Link between the Superconducting Dome and Spin-Orbit Interaction in the (111) LaAlO$_3$/SrTiO$_3$ Interface

## TL;DR

This study explores how superconductivity and spin-orbit interaction are interconnected in the (111) LaAlO$_3$/SrTiO$_3$ interface, revealing a correlated dome-shaped dependence on gate voltage and suggesting a nontrivial link between them.

## Contribution

It demonstrates a direct correlation between superconductivity and spin-orbit interaction in the (111) LaAlO$_3$/SrTiO$_3$ interface, supported by experimental measurements and proposing explanations for unconventional behavior.

## Key findings

- Superconductivity exhibits a dome-shaped dependence on gate voltage.
- Spin-orbit interaction follows the same gate voltage dependence as $T_c$.
- Enhanced upper critical fields suggest a nontrivial link between superconductivity and spin-orbit interaction.

## Abstract

We measure the gate voltage ($V_g$) dependence of the superconducting properties and the spin-orbit interaction in the (111)-oriented LaAlO$_3$/SrTiO$_3$ interface. Superconductivity is observed in a dome-shaped region in the carrier density-temperature phase diagram with the maxima of superconducting transition temperature $T_c$ and the upper critical fields lying at the same $V_g$. The spin-orbit interaction determined from the superconducting parameters and confirmed by weak-antilocalization measurements follows the same gate voltage dependence as $T_c$. The correlation between the superconductivity and spin-orbit interaction as well as the enhancement of the parallel upper critical field, well beyond the Chandrasekhar-Clogston limit suggest that superconductivity and the spin-orbit interaction are linked in a nontrivial fashion. We propose possible scenarios to explain this unconventional behavior.