Valley-exchange coupling probed by angle-resolved photoluminescence

Abstract

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 dispersionand its signatures in optical spectra

References in corpus (5)

• Valley Zeeman Effect in Elementary Optical Excitations of a Monolayer WSe2
• Valley Splitting and Polarization by the Zeeman Effect in Monolayer MoSe2
• Phonon Sidebands in Transition Metal Dichalcogenides
• Fundamental exciton linewidth broadening in monolayer transition metal dichalcogenides
• Criteria for deterministic single-photon emission in two-dimensional atomic crystals

Cited by in corpus (2)

• Interlayer exciton polaritons in homobilayers of transition metal dichalcogenides
• Laser-patterned submicron Bi2Se3-WS2 pixels with tunable circular polarization at room temperature