APS Logo

Probing exciton dissociation in C60/Au(111) using TR-ARPES

ORAL

Abstract

A limiting factor of organic photovoltaic devices is the generation of strongly bound excitons upon photoexcitation which decay quickly (10s - 100s fs). Interfaces often play a role in driving exciton dissociation in devices but the mechanisms that result in efficient charge separation are still not well understood.



While optical techniques have been used to study the ultrafast response of organic semiconductors for several years, a lack of momentum resolution has limited their interpretation. Time- and angle-resolved photoemission spectroscopy (TR-ARPES) is a technique that allows a user to visualize the energy-momentum landscape of a material and enables real-time observation of the material’s response to photoexcitation.



Using TR-ARPES to track the dynamics and resolve the momentum dependent dispersion of the excitations, we are able to probe excitons in C60 and charge separation at the C60/Au(111) interface. We do this for a variety of film thicknesses grown using our two-stage growth method to produce highly-ordered films [1]. This will allow us to better understand the processes that occur post-photoexcitation both at and away from the organic-metal interface.



[1] Tully, Greenwood, Burke, et al., J. Phys. Chem. C, 128, 42 (2024)

–

Publication: A. Tully, R. Greenwood, S.A. Burke et al., Two-stage growth for highly ordered epitaxial C60 films on Au(111), J. Phys. Chem. C 2024, 128, 42, 18128–18134

Presenters

  • Rysa Greenwood

    University of British Columbia, The University of British Columbia

Authors

  • Rysa Greenwood

    University of British Columbia, The University of British Columbia

  • Alexandra Tully

    The University of British Columbia

  • MengXing Na

    University of British Columbia

  • Bradley G Guislain

    University of British Columbia

  • Sergey Zhdanovich

    University of British Columbia

  • Jerry I Dadap

    University of British Columbia, The University of British Columbia

  • Giorgio Levy

    The University of British Columbia, University of British Columbia

  • Arthur K Mills

    University of British Columbia, The University of British Columbia

  • Matteo Michiardi

    University of British Columbia

  • Andrea Damascelli

    University of British Columbia

  • Sarah Burke

    University of British Columbia, The University of British Columbia

  • David Jones

    University of British Columbia, The University of British Columbia