Direct Visualization of Exciton Transport in Semiconductor Quantum Dot Nanostructures Using Time-Resolved Superresolution Microscopy

ORAL

Abstract

A time-resolved superresolution microscope to localize single emitters with nanometer precision and image their lifetimes with sub-nanosecond time resolution is described. This technique has been used to image semiconductor quantum dot (QD) nanostructures composed of single QD emitters that interact via resonance energy transfer. Photoemission from the nanostructures is imaged onto a 2x2 optical fiber array, and the fiber outputs are monitored using time-correlated single photon counting. The relative intensities reveal changes in the emission center as the QDs blink on and off. Emission centers separated by 10-nm or less can be distinguished based on changes in intensity and lifetime that occur when energy is transferred from donor to acceptor QDs. The distribution of centroid positions provide a direct visualization of the energy transport pathway through the nanostrucure.

*This work was funded by the Los Alamos Laboratory-Directed Research and Development Exploratory Research Program (20180189ER) and performed, in part, at the Center for Integrated Nanotechnologies, a User Facility operated for the U.S. Department of Energy (DOE) Office of Science. AVO acknowledges the Los Alamos Institute for Materials Science for a Rapid Response grant. LA-UR-19-30557, unlimited release.

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Presenters

  • Alan Van Orden

    • Department of Chemistry, Colorado State University

Authors

  • Alan Van Orden

    • Department of Chemistry, Colorado State University

  • Megan Dunlap

    • Department of Chemistry, Colorado State University

  • Duncan P. Ryan

    • Center for Integrated Nanotechnologies, Los Alamos National Laboratory

  • Peter Goodwin

    • Center for Integrated Nanotechnologies, Los Alamos National Laboratory

  • James Werner

    • Center for Integrated Nanotechnologies, Los Alamos National Laboratory

  • Jennifer A Hollingsworth

    • Center for Integrated Nanotechnologies, Los Alamos National Laboratory
    • Los Alamos National Laboratory

  • Martin Paul Gelfand

    • Department of Physics, Colorado State University