Exciton-exciton annihilation and biexciton stimulated emission in graphene nanoribbons
Soavi G, Dal Conte S, Manzoni C, Viola D, Narita A, Hu Y, Feng X, Hohenester U, Molinari E, Prezzi D, Muellen K, Cerullo G (2016)
Publication Type: Journal article
Publication year: 2016
Journal
Book Volume: 7
Article Number: 11010
DOI: 10.1038/ncomms11010
Abstract
Graphene nanoribbons display extraordinary optical properties due to one-dimensional quantum-confinement, such as width-dependent bandgap and strong electron-hole interactions, responsible for the formation of excitons with extremely high binding energies. Here we use femtosecond transient absorption spectroscopy to explore the ultrafast optical properties of ultranarrow, structurally well-defined graphene nanoribbons as a function of the excitation fluence, and the impact of enhanced Coulomb interaction on their excited states dynamics. We show that in the high-excitation regime biexcitons are formed by nonlinear exciton-exciton annihilation, and that they radiatively recombine via stimulated emission. We obtain a biexciton binding energy of â ‰250 meV, in very good agreement with theoretical results from quantum Monte Carlo simulations. These observations pave the way for the application of graphene nanoribbons in photonics and optoelectronics.
Involved external institutions
Politecnico di Milano
Italy (IT)
Consiglio Nazionale delle Ricerche (CNR) / National Research Council of Italy
Italy (IT)
Max-Planck-Institut für Polymerforschung (MPI-P) / Max Planck Institute for Polymer Research
Germany (DE)
Karl-Franzens-Universität Graz
Austria (AT)
Università degli Studi di Modena e Reggio Emilia (UNIMORE)
Italy (IT)
Italy (IT)
Consiglio Nazionale delle Ricerche (CNR) / National Research Council of Italy
Italy (IT)
Max-Planck-Institut für Polymerforschung (MPI-P) / Max Planck Institute for Polymer Research
Germany (DE)
Karl-Franzens-Universität Graz
Austria (AT)
Università degli Studi di Modena e Reggio Emilia (UNIMORE)
Italy (IT)
How to cite
APA:
Soavi, G., Dal Conte, S., Manzoni, C., Viola, D., Narita, A., Hu, Y.,... Cerullo, G. (2016). Exciton-exciton annihilation and biexciton stimulated emission in graphene nanoribbons. Nature Communications, 7. https://doi.org/10.1038/ncomms11010
MLA:
Soavi, Giancarlo, et al. "Exciton-exciton annihilation and biexciton stimulated emission in graphene nanoribbons." Nature Communications 7 (2016).
BibTeX: Download