title: Long-Lived Hole Spin/Valley Polarization Probed by Kerr Rotation in Monolayer WSe2.
abstract: Time-resolved Kerr rotation and photoluminescence measurements are performed on MOCVD-grown monolayer tungsten diselenide (WSe2). We observe a surprisingly long-lived Kerr rotation signal (∼80 ns) at 10 K, which is attributed to spin/valley polarization of the resident holes. This polarization is robust to transverse magnetic field (up to 0.3 T). Wavelength-dependent measurements reveal that only excitation near the free exciton energy generates this long-lived spin/valley polarization.
authors.affiliation: Applied Physics Program, University of Michigan , 450 Church Street, Ann Arbor, Michigan 48109, United States.
authors.forename: Xinlin
authors.initials: X
authors.lastname: Song
authors.forename: Saien
authors.initials: S
authors.lastname: Xie
authors.forename: Kibum
authors.initials: K
authors.lastname: Kang
authors.affiliation: Kavli Institute at Cornell for Nanoscale Science , 245 East Avenue, Ithaca, New York 14853, United States.
authors.forename: Jiwoong
authors.initials: J
authors.lastname: Park
authors.affiliation: Department of Physics, University of Michigan , 450 Church Street, Ann Arbor, Michigan 48109, United States.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Sih
keywords: Kerr rotation; Tungsten diselenide; exciton; photoluminescence; spin polarization