Event Details
Coupling perovskite quantum fot pairs in solution using double nanohole optical tweezers
Presenter: Hao Zhang
Supervisor:
Date: Tue, March 29, 2022
Time: 12:00:00 - 13:00:00
Place: ZOOM - Please see below.
ABSTRACT
Zoom link: https://uvic.zoom.us/j/86313643797?pwd=NjgxVDhPVWtwQjV5UkpoY2RUNXF3QT09
Meeting ID: 863 1364 3797
Password: 557682
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Summary: Perovskite quantum dots (PQDs) provide a robust solution-based approach to achieve efficient solar cells, bright light emitting devices, quantum sources of highly coherent single photons and superfluorescence between strongly coupled ensembles. In these applications and others, quantifying heterogeneity and understanding coupling between dots is critical. To achieve this for PQDs in solution, we use double-nanohole (DNH) optical trapping. We are able to size individual dots from thermal fluctuations and correlate this to emission energy shifts from quantum confinement, allowing for single particle analysis of heterogeneous broadening. We use the DNH to trap a second dot, which allows us to observe the coupling between dots. We observe a systematic red-shift of 1.1±0.6 meV in the emission wavelength upon multiple repeated measurements. Theoretical analysis shows that the observed shift is consistent with Forster resonant energy transfer, which has been proposed to obtain entanglement between colloidal quantum dots for quantum information applications. This work enables future in situ control of PQD growth as well as detailed studies of the coupling between small assemblies of quantum dots with quantum information applications in mind.