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Photoconductivite et photoemission de diamant(s) sous irradiation XUV femtoseconde

Guillaume Petite·Jerome Gaudin·Ghita Geoffroy·Stephane Guizard·Stephane Esnouf·Valerio Olevano·Serguei M. Klimentov·Pavel A. Pivovarov·Serguei V. Garnov·Bertrand Carre·Patrick Martin·Andrei Belsky
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Abstract

We report a study of the photoconductivity (PC) induced in different types of diamonds (type IIa single crystals and CVD) by femtosecond XUV pulses (high order harmonics - up to 19th - of a titanium doped laser). We also reprot UPS spectras obtained with harmonics 13 to 29. Depending on the harmonic's order, the PC signal first increases (orders 9 to 13) and then decreases. If the increase is easily interpreted as resulting from a carrier multiplication process, the further decrease has not yet received an explanation. The UPS measurements also suggest a strong effect of the plasmon relaxation on the carrier multiplication process. Finally, we performed a preliminary GW ab-initio calculation of the carriers lifetime, acounting for electron-electron interactions. In the near-bandgap region, it behaves approximatively according to the Fermi-liquid model, from which it strongly departs at higher energies, which is attributed to band-structure effects and to plasmon excitations.

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Guillaume Petite, Jerome Gaudin, Ghita Geoffroy, Stephane Guizard, Stephane Esnouf, Valerio Olevano, Serguei M. Klimentov, Pavel A. Pivovarov, Serguei V. Garnov, Bertrand Carre, Patrick Martin, Andrei Belsky. 2004-07-15. Photoconductivite et photoemission de diamant(s) sous irradiation XUV femtoseconde. https://arxiv.org/abs/cond-mat/0407402

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