# Shubnikov-de Haas oscillations in optical conductivity of monolayer MoSe$_2$

## TL;DR

This study demonstrates how exciton-hole interactions in monolayer MoSe$_2$ lead to Shubnikov-de Haas oscillations observable through optical spectroscopy, revealing quantum Hall physics in a 2D semiconductor.

## Contribution

It introduces a novel optical method to probe Landau level occupation and quantum Hall effects via excitonic resonances in monolayer MoSe$_2$.

## Key findings

- Observation of Landau level-dependent oscillations in excitonic properties.
- Correlation between exciton resonance shifts and quantum Hall states.
- Evidence of strong exciton-carrier interactions in 2D materials.

## Abstract

We report polarization-resolved resonant reflection spectroscopy of a charge-tunable atomically-thin valley semiconductor hosting tightly bound excitons coupled to a dilute system of fully spin- and valley-polarized holes in the presence of a strong magnetic field. We find that exciton-hole interactions manifest themselves in hole-density dependent, Shubnikov-de Haas-like oscillations in the energy and line broadening of the excitonic resonances. These oscillations are evidenced to be precisely correlated with the occupation of Landau levels, thus demonstrating that strong interactions between the excitons and Landau-quantized itinerant carriers enable optical investigation of quantum-Hall physics in transition metal dichalcogenides.