Polarization and time-resolved photoluminescence spectroscopy of excitons in MoSe2 monolayers

نویسندگان

  • G. Wang
  • E. Palleau
  • T. Amand
  • S. Tongay
  • X. Marie
  • B. Urbaszek
چکیده

We investigate valley exciton dynamics in MoSe2 monolayers in polarizationand time-resolved photoluminescence (PL) spectroscopy at 4K. Following circularly polarized laser excitation, we record a low circular polarization degree of the PL of typically ≤ 5%. This is about 10 times lower than the polarization induced under comparable conditions in MoS2 and WSe2 monolayers. The evolution of the exciton polarization as a function of excitation laser energy and power is monitored in PL excitation (PLE) experiments. Fast PL emission times are recorded for both the neutral exciton of ≤ 3 ps and for the charged exciton (trion) of 12 ps.

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تاریخ انتشار 2015