Title :

Photocycle of point defects in highly- and weakly-germanium doped silica revealed by transient absorption measurements with femtosecond tunable pump

Author(s) :

de Michele, V. [Auteur]
Laboratoire Hubert Curien [LabHC]
Università degli studi di Palermo - University of Palermo
Sciortino, A. [Auteur]
Università degli studi di Palermo - University of Palermo
Bouet, M. [Auteur]
Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 [PhLAM]
Bouwmans, G. [Auteur]
Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 [PhLAM]
Agnello, S. [Auteur]
Università degli studi di Palermo - University of Palermo
Messina, F. [Auteur]
Università degli studi di Palermo - University of Palermo
Cannas, M. [Auteur]
Università degli studi di Palermo - University of Palermo
Boukenter, A. [Auteur]
Laboratoire Hubert Curien [LabHC]
Marin, E. [Auteur]
Laboratoire Hubert Curien [LabHC]
Girard, S. [Auteur]
Laboratoire Hubert Curien [LabHC]
Ouerdane, Y. [Auteur]
Laboratoire Hubert Curien [LabHC]

Journal title :

Scientific Reports

Pages :

9223

Publisher :

Nature Publishing Group

Publication date :

2022-12

ISSN :

2045-2322

HAL domain(s) :

Physique [physics]/Physique [physics]/Optique [physics.optics]

English abstract : [en]

Abstract We report pump-probe transient absorption measurements addressing the photocycle of the Germanium lone pair center (GLPC) point defect with an unprecedented time resolution. The GLPC is a model point defect with ...
Show more >Abstract We report pump-probe transient absorption measurements addressing the photocycle of the Germanium lone pair center (GLPC) point defect with an unprecedented time resolution. The GLPC is a model point defect with a simple and well-understood electronic structure, highly relevant for several applications. Therefore, a full explanation of its photocycle is fundamental to understand the relaxation mechanisms of such molecular-like systems in solid state. The experiment, carried out exciting the sample resonantly with the ultraviolet (UV) GLPC absorption band peaked at 5.1 eV, gave us the possibility to follow the defect excitation-relaxation dynamics from the femto-picosecond to the nanosecond timescale in the UV–visible range. Moreover, the transient absorption signal was studied as a function of the excitation photon energy and comparative experiments were conducted on highly- and weakly-germanium doped silica glasses. The results offer a comprehensive picture of the relaxation dynamics of GLPC and allow observing the interplay between electronic transitions localized on the defect and those related to bandgap transitions, providing a clear evidence that the role of dopant high concentration is not negligible in the earliest dynamics.Show less >

Language :

Anglais

Popular science :

Non

Collections :

• Laboratoire de Physique des Lasers, Atomes et Molécules (PhLAM) - UMR 8523

Source :

Harvested from HAL