Unveiling exciton formation: exploring the early stages in time, energy and momentum domain

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Bibliographic Details
Main Authors:	Gosetti, Valentina, Cervantes-Villanueva, Jorge, Mor, Selene, Sangalli, Davide, García-Cristóbal, Alberto, Molina-Sánchez, Alejandro, Agekyan, Vadim F., Tuniz, Manuel, Puntel, Denny, Bronsch, Wibke, Cilento, Federico, Pagliara, Stefania
Format:	Preprint
Published:	2024
Subjects:	Materials Science
Online Access:	Acceder al recurso
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author	Gosetti, Valentina Cervantes-Villanueva, Jorge Mor, Selene Sangalli, Davide García-Cristóbal, Alberto Molina-Sánchez, Alejandro Agekyan, Vadim F. Tuniz, Manuel Puntel, Denny Bronsch, Wibke Cilento, Federico Pagliara, Stefania
author_facet	Gosetti, Valentina Cervantes-Villanueva, Jorge Mor, Selene Sangalli, Davide García-Cristóbal, Alberto Molina-Sánchez, Alejandro Agekyan, Vadim F. Tuniz, Manuel Puntel, Denny Bronsch, Wibke Cilento, Federico Pagliara, Stefania
contents	Resolving the early-stage dynamics of exciton formation following non-resonant photoexcitation in time, energy, and momentum is quite challenging due to their inherently fast timescales and the proximity of the excitonic state to the bottom of the conduction band. In this study, by combining time- and angle-resolved photoemission spectroscopy with \mathit{ab initio} numerical simulations, we capture the timing of the early-stage exciton dynamics in energy and momentum, starting from the photoexcited population in the conduction band, progressing through the formation of free excitons, and ultimately leading to their trapping in lattice deformations. The chosen material is bismuth tri-iodide ($BiI_3$), a layered semiconductor with a rich landscape of excitons in the electronic structure both in bulk and in monolayer form. The obtained results, providing a full characterization of the exciton formation, elucidate the early stages of the physical phenomena underlying the operation of the ultrafast semiconductor device.
format	Preprint
id	arxiv_https___arxiv_org_abs_2412_02507
institution	arXiv
publishDate	2024
record_format	arxiv
spellingShingle	Unveiling exciton formation: exploring the early stages in time, energy and momentum domain Gosetti, Valentina Cervantes-Villanueva, Jorge Mor, Selene Sangalli, Davide García-Cristóbal, Alberto Molina-Sánchez, Alejandro Agekyan, Vadim F. Tuniz, Manuel Puntel, Denny Bronsch, Wibke Cilento, Federico Pagliara, Stefania Materials Science Resolving the early-stage dynamics of exciton formation following non-resonant photoexcitation in time, energy, and momentum is quite challenging due to their inherently fast timescales and the proximity of the excitonic state to the bottom of the conduction band. In this study, by combining time- and angle-resolved photoemission spectroscopy with \mathit{ab initio} numerical simulations, we capture the timing of the early-stage exciton dynamics in energy and momentum, starting from the photoexcited population in the conduction band, progressing through the formation of free excitons, and ultimately leading to their trapping in lattice deformations. The chosen material is bismuth tri-iodide ($BiI_3$), a layered semiconductor with a rich landscape of excitons in the electronic structure both in bulk and in monolayer form. The obtained results, providing a full characterization of the exciton formation, elucidate the early stages of the physical phenomena underlying the operation of the ultrafast semiconductor device.
title	Unveiling exciton formation: exploring the early stages in time, energy and momentum domain
topic	Materials Science
url	https://arxiv.org/abs/2412.02507

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