Isolating Exciton Dissociation Pathways in ReSe$_{\text{2}}$

Bradley G. Guislain; Rysa Greenwood; Matteo Michiardi; Giorgio Levy; Sergey Zhdanovich; Jerry Icban Dadap; Sydney K. Y. Dufresne; Arthur K. Mills; Dario Armanno; Shawn Lapointe; Francesco Goto; Nicolas Gauthier; Fabio Boschini; Andrea Damascelli; Ziliang Ye; David J. Jones

arXiv · 2604.11906

Isolating Exciton Dissociation Pathways in ReSe$_{\text{2}}$

Bradley G. Guislain·Rysa Greenwood·Matteo Michiardi·Giorgio Levy·Sergey Zhdanovich·Jerry Icban Dadap·Sydney K. Y. Dufresne·Arthur K. Mills·Dario Armanno·Shawn Lapointe·Francesco Goto·Nicolas Gauthier·Fabio Boschini·Andrea Damascelli·Ziliang Ye·David J. Jones

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Abstract

Strongly bound excitons dominate the optical response in many van der Waals semiconductors, yet distinguishing between the different microscopic processes governing exciton dissociation remains challenging. Using time- and angle-resolved photoemission spectroscopy (TR-ARPES), we independently track exciton and band-edge carrier populations in bulk ReSe$_{\text{2}}$ under resonant excitation. By studying the fluence dependence and polarization-controlled exciton density dependence of the exciton dissociation process, we distinguish between competing processes and identify exciton photoionization as the microscopic dissociation mechanism. These results establish a population-resolved strategy for resolving exciton-to-carrier conversion pathways in strongly excitonic materials.

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Bradley G. Guislain, Rysa Greenwood, Matteo Michiardi, Giorgio Levy, Sergey Zhdanovich, Jerry Icban Dadap, Sydney K. Y. Dufresne, Arthur K. Mills, Dario Armanno, Shawn Lapointe, Francesco Goto, Nicolas Gauthier, Fabio Boschini, Andrea Damascelli, Ziliang Ye, David J. Jones. 2026-04-13. Isolating Exciton Dissociation Pathways in ReSe$_{\text{2}}$. https://arxiv.org/abs/2604.11906

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