2018/05/25 by Alessandro Surrente, Lukasz Klopotowski, Nan Zhang +9 · 1 citation
Physics and Astronomy · #cond-mat.mes-hall
paper · pdf · doi:10.1021/acs.nanolett.8b01484
just accepted in Nano Letters, DOI: 10.1021/acs.nanolett.8b01484
arxiv created 2018/05/25 · arxiv updated 2018/05/28
Degenerate extrema in the energy dispersion of charge carriers in solids, also referred to as valleys, can be regarded as a binary quantum degree of freedom, which can potentially be used to implement valleytronic concepts in van der Waals heterostructures based on transition metal dichalcogenides. Using magneto-photoluminescence spectroscopy, we achieve a deeper insight into the valley polarization and depolarization mechanisms of interlayer excitons formed across a MoS2/MoSe2/MoS2 heterostructure. We account for the non-trivial behavior of the valley polarization as a function of the magnetic field by considering the interplay between exchange interaction and phonon mediated intervalley scattering in a system consisting of Zeeman-split energy levels. Our results represent a crucial step towards the understanding of the properties of interlayer excitons, with strong implications for the implementation of atomically thin valleytronic devices.