title: Opto-valleytronic imaging of atomically thin semiconductors.
abstract: Transition metal dichalcogenide semiconductors represent elementary components of layered heterostructures for emergent technologies beyond conventional optoelectronics. In their monolayer form they host electrons with quantized circular motion and associated valley polarization and valley coherence as key elements of opto-valleytronic functionality. Here, we introduce two-dimensional polarimetry as means of direct imaging of the valley pseudospin degree of freedom in monolayer transition metal dichalcogenides. Using MoS2as a representative material with valley-selective optical transitions, we establish quantitative image analysis for polarimetric maps of extended crystals, and identify valley polarization and valley coherence as sensitive probes of crystalline disorder. Moreover, we find site-dependent thermal and non-thermal regimes of valley-polarized excitons in perpendicular magnetic fields. Finally, we demonstrate the potential of wide-field polarimetry for rapid inspection of opto-valleytronic devices based on atomically thin semiconductors and heterostructures.
authors.affiliation: Fakultät für Physik, Munich Quantum Center, and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München, D-80539 München, Germany.
authors.forename: Andre
authors.initials: A
authors.lastname: Neumann
authors.affiliation: Fakultät für Physik, Munich Quantum Center, and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München, D-80539 München, Germany.
authors.forename: Jessica
authors.initials: J
authors.lastname: Lindlau
authors.affiliation: Fakultät für Physik, Munich Quantum Center, and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München, D-80539 München, Germany.
authors.forename: Léo
authors.initials: L
authors.lastname: Colombier
authors.affiliation: Fakultät für Physik, Munich Quantum Center, and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München, D-80539 München, Germany.
authors.forename: Manuel
authors.initials: M
authors.lastname: Nutz
authors.affiliation: Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, USA.
authors.forename: Sina
authors.identifier: 0000-0003-4650-1997
authors.initials: S
authors.lastname: Najmaei
authors.affiliation: Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Lou
authors.affiliation: MPA-11 Materials Synthesis and Integrated Devices, Materials Physics and Applications Division, Los Alamos National Laboratory (LANL), Los Alamos, New Mexico 87545, USA.
authors.forename: Aditya D
authors.initials: AD
authors.lastname: Mohite
authors.affiliation: MPA-11 Materials Synthesis and Integrated Devices, Materials Physics and Applications Division, Los Alamos National Laboratory (LANL), Los Alamos, New Mexico 87545, USA.
authors.forename: Hisato
authors.initials: H
authors.lastname: Yamaguchi
authors.affiliation: Fakultät für Physik, Munich Quantum Center, and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München, D-80539 München, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Högele