Origin of power-law fluorescence blinking in semiconductor nanocrystals · revision history

Revision 2

Accepted · core change · record

Changes against revision 1:

Title
Origin of power-law fluorescence blinking in semiconductor nanocrystals
Plain
A single tiny crystal of CdSe or perovskite glows, then goes dark, then glows again, with on and off periods spread over every timescale from microseconds to minutes. Why the durations follow a power law, instead of having one typical time, is unknown.
Precise · changed · core
Revision 1: Single CdSe, CdSe/CdS and CsPbBr3 nanocrystals show on and off duration distributions $P(t) \sim t^{-\alpha}$ with $\alpha \sim 1.5$ over about six decades, plus partially bright grey states. Determine the microscopic mechanism (Auger quenching in charged nanocrystals, hot-carrier trapping with fluctuating rates, diffusing energy levels of surface traps) that yields the power law and its exponent, consistent with photon statistics, lifetime-intensity correlations and suppression in thick-shell structures. An answer is a mechanism reproducing $P(t)$ and its dependence on excitation intensity.
Revision 2: Single CdSe, CdSe/CdS and $\mathrm{CsPbBr_3}$ nanocrystals show on and off duration distributions $P(t) \sim t^{-\alpha}$ with $\alpha \sim 1.5$ over about six decades, plus partially bright grey states. Determine the microscopic mechanism (Auger quenching in charged nanocrystals, hot-carrier trapping with fluctuating rates, diffusing energy levels of surface traps) that yields the power law and its exponent, consistent with photon statistics, lifetime-intensity correlations and suppression in thick-shell structures. An answer is a mechanism reproducing $P(t)$ and its dependence on excitation intensity.
Settled by
Single-particle measurements correlating blinking statistics with in situ charge state and trap spectroscopy, reproduced by a microscopic model with measured parameters.
Kind
phenomenon
Answer type
mechanism
References
(empty)
Literature status
open
Status note
(empty)
Posed since
1996

Decisions