# Zeeman splitting via spin-valley-layer coupling in bilayer MoTe2

## TL;DR

This paper demonstrates that Zeeman splitting persists in bilayer MoTe2 due to spin-valley-layer coupling, enabling magnetic control of polarization and advancing bilayer TMDs for spin-valleytronics.

## Contribution

It reveals the persistence of Zeeman splitting in bilayer MoTe2 through spin-valley-layer locking, despite restored inversion symmetry.

## Key findings

- Zeeman splitting occurs without lifting valley degeneracy in bilayers.
- Circular polarization can be tuned from -27% to 27% with magnetic field.
- Bilayer MoTe2 is a promising platform for spin-valley quantum gates.

## Abstract

Atomically thin transition metal dichalcogenides (TMDs) possess coupling of spin and valley degrees of freedom, making them promising for spin-valleytronics. ln monolayer TMDs, the emission helicity is locked to the valleys as a consequence of spin-orbit coupling and inversion symmetry breaking, leading to a valley analog of Zeeman effect in presence of out-of-plane magnetic field. As inversion symmetry is recovered in bilayers, the emission helicity should no longer be locked to the valleys. Here we show that Zeeman splitting, however, still persists in bilayers, as a result of an additional degree of freedom viz., the layer pseudospin and spin-valley-layer locking. In contrast to monolayer, Zeeman splitting here exists without lifting valley degeneracy. The degree of circularly polarized photoluminescence can be tuned with magnetic field from $-27\%$ to $27\%$. Our results demonstrate the control of degree of freedom in bilayer with magnetic field, which, together with previous electric field control, makes bilayer a promising platform for spin-valley quantum gates based on magnetoelectric effects.