Six-Body and Eight-Body Exciton States in Monolayer WSe_{2}

Dinh Van Tuan; Su-Fei Shi; Xiaodong Xu; Scott A Crooker; Hanan Dery

doi:10.1103/PhysRevLett.129.076801

Six-Body and Eight-Body Exciton States in Monolayer WSe_{2}

Phys Rev Lett. 2022 Aug 12;129(7):076801. doi: 10.1103/PhysRevLett.129.076801.

Authors

Dinh Van Tuan¹, Su-Fei Shi^{2

3}, Xiaodong Xu^{4

5}, Scott A Crooker⁶, Hanan Dery^{1

7}

Affiliations

¹ Department of Electrical and Computer Engineering, University of Rochester, Rochester, New York 14627, USA.
² Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, USA.
³ Department of Electrical, Computer and Systems Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, USA.
⁴ Department of Physics, University of Washington, Seattle, Washington 98195, USA.
⁵ Department of Materials Science and Engineering, University of Washington, Seattle, Washington 98195, USA.
⁶ National High Magnetic Field Laboratory, Los Alamos, New Mexico 87545, USA.
⁷ Department of Physics and Astronomy, University of Rochester, Rochester, New York 14627, USA.

PMID: 36018693
DOI: 10.1103/PhysRevLett.129.076801

Abstract

In the archetypal monolayer semiconductor WSe_{2}, the distinct ordering of spin-polarized valleys (low-energy pockets) in the conduction band allows for studies of not only simple neutral excitons and charged excitons (i.e., trions), but also more complex many-body states that are predicted at higher electron densities. We discuss magneto-optical measurements of electron-rich WSe_{2} monolayers and interpret the spectral lines that emerge at high electron doping as optical transitions of six-body exciton states ("hexcitons") and eight-body exciton states ("oxcitons"). These many-body states emerge when a photoexcited electron-hole pair interacts simultaneously with multiple Fermi seas, each having distinguishable spin and valley quantum numbers. In addition, we explain the relations between dark trions and satellite optical transitions of hexcitons in the photoluminescence spectrum.