Negatively Charged and Dark Excitons in CsPbBr3 Perovskite Nanocrystals Revealed by High Magnetic Fields

作者:Canneson Damien; Shornikova Elena V; Yakovlev Dmitri R; Rogge Tobias; Mitioglu Anatolie A; Ballottin Mariana V; Christianen Peter C M; Lhuillier Emmanuel; Bayer Manfred; Biadala Louis*
来源:Nano Letters, 2017, 17(10): 6177-6183.
DOI:10.1021/acs.nanolett.7b02827

摘要

The optical properties of colloidal cesium lead halide perovskite (CsPbBr3) nanocrystals are examined by time-resolved and polarization-resolved spectroscopy in high, magnetic fields up to 30 T. We unambiguously show that at cryogenic temperatures the emission is dominated by recombination of negatively charged excitons with radiative decay time of 300 ps. The additional long-lived emission; which decay time shortens from 40 down to 8 ns and in which the decay time shortens and relative amplitude increases in high magnetic fields, evidences the presence of a dark exciton. We evaluate g-factors of the bright,exciton g(x) = +2,4, the electron g(e) = +2.18, and the hole g(h) = 0.22.

  • 出版日期2017-10