EP05.07.22 : Photoluminescence Up-Conversion in CsPbBr3 Nanocrystals

5:00 PM–7:00 PM Apr 5, 2018 (America - Denver)

PCC North, 300 Level, Exhibit Hall C-E

Yurii Morozov1 Shubin Zhang1 Masaru Kuno1

1, University of Notre Dame, Notre Dame, Indiana, United States

Laser refrigeration of semiconductors is an emerging field of science with exciting possible applications, one of which is optical refrigerator operating in the sub-10 K regime. Recently, it has been shown that hybrid perovskites can exhibit laser cooling through photoluminescence (PL) up-conversion. Here, we investigate PL up-conversion in CsPbBr3 nanocrystals (NCs) using temperature-dependent, frequency-dependent, and excitation intensity-dependent up-conversion measurements. We conclude that PL up-conversion is phonon-assisted and demonstrate first observation of PL up-conversion from CsPbBr3 NCs at both the ensemble and single-NC levels. Ensemble up-conversion efficiencies are estimated to be on the order of 75% for a ΔE = 23 meV excitation detuning into the NC bandgap.