Valley-exchange coupling probed by angle-resolved photoluminescence
Journal article, 2022

The optical properties of monolayer transition metal dichalcogenides are dominated by tightly-bound excitons. They form at distinct valleys in reciprocal space, and can interact via the valley-exchange coupling, modifying their dispersion considerably. Here, we predict that angle-resolved photoluminescence can be used to probe the changes of the excitonic dispersion. The exchange-coupling leads to a unique angle dependence of the emission intensity for both circularly and linearly-polarised light. We show that these emission characteristics can be strongly tuned by an external magnetic field due to the valley-specific Zeeman-shift. We propose that angle-dependent photoluminescence measurements involving both circular and linear optical polarisation as well as magnetic fields should act as strong verification of the role of valley-exchange coupling on excitonic dispersion and its signatures in optical spectra.

Author

Joshua Thompson

Chalmers, Physics, Condensed Matter and Materials Theory

Samuel Brem

Philipps University Marburg

Hanlin Fang

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Technology

Carlos Anton-Solanas

The Carl von Ossietzky University of Oldenburg

Bo Han

The Carl von Ossietzky University of Oldenburg

Hangyong Shan

The Carl von Ossietzky University of Oldenburg

Saroj Prasad Dash

2D-Tech

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Witlef Wieczorek

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Technology

Christian Schneider

The Carl von Ossietzky University of Oldenburg

Ermin Malic

Philipps University Marburg

2D-Tech

Chalmers, Physics, Condensed Matter and Materials Theory

Nanoscale Horizons

2055-6756 (ISSN) 2055-6764 (eISSN)

Vol. 7 1 77-84

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Subject Categories

Atom and Molecular Physics and Optics

Other Physics Topics

Condensed Matter Physics

DOI

10.1039/d1nh00302j

PubMed

34796891

More information

Latest update

2/29/2024