Moir\'e Engineering of Spin-Orbit Coupling in Twisted Platinum Diselenide

TL;DR

This study explores how moiré engineering in twisted platinum diselenide bilayers can tune spin-orbit interactions, leading to novel electronic phases including exotic superconductivity and entangled density waves.

Contribution

It demonstrates the ability to control Rashba spin-orbit coupling strength via twist angles, creating a platform for exploring new correlated electronic phases.

Findings

Moiré patterns enable tuning of spin-orbit interactions.

Effective triangular lattice can be realized with twist control.

Interaction-driven phases include exotic superconductivity and density waves.

Abstract

We study the electronic structure and correlated phases of twisted bilayers of platinum diselenide using large-scale ab initio simulations combined with the functional renormalization group. PtSe$_2$ is a group-X transition metal dichalcogenide, which hosts emergent flat bands at small twist angles in the twisted bilayer. Remarkably, we find that moir\'e engineering can be used to tune the strength of Rashba spin-orbit interactions, altering the electronic behavior in a novel manner. We reveal that an effective triangular lattice with a twist-controlled ratio between kinetic and spin-orbit coupling scales can be realized. Even dominant spin-orbit coupling can be accessed in this way and we discuss consequences for the interaction driven phase diagram, which features pronounced exotic superconducting and entangled spin-charge density waves.