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arXiv · 0908.0406

Disentangling thermal and non-thermal excited states in a charge-transfer insulator by time-and-frequency resolved pump-probe spectroscopy

Claudio Giannetti·Goran Zgrablic·Cristina Consani·Alberto Crepaldi·Damiano Nardi·Gabriele Ferrini·G. Dhalenne·A. Revcolevschi·Fulvio Parmigiani
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Abstract

Time-and-frequency resolved pump-probe optical spectroscopy is used to investigate the effect of the impulsive injection of delocalized excitations through a charge-transfer process in insulating CuGeO3. A large broadening of the charge-transfer edge is observed on the sub-ps timescale. The modification of this spectral feature can not be attributed to the local increase of the effective temperature, as a consequence of the energy absorbed by the pump pulse. The measured modifications of the optical properties of the system are consistent with the creation of a non-thermal state, metastable on the ps timescale, after the pump-induced impulsive modification of the electron interactions.

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Claudio Giannetti, Goran Zgrablic, Cristina Consani, Alberto Crepaldi, Damiano Nardi, Gabriele Ferrini, G. Dhalenne, A. Revcolevschi, Fulvio Parmigiani. 2009-08-04. Disentangling thermal and non-thermal excited states in a charge-transfer insulator by time-and-frequency resolved pump-probe spectroscopy. https://doi.org/10.1103/physrevb.80.235129

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