Nanoseconde study of spin state transition induced by a single nanosecond laser shot on [Fe(NH₂trz)₃] compounds inside and outside their thermal hysteresis loops

G. Gallé (1) , Jérôme Degert (1) , Cindy Mauriac (2) , Céline Etrillard (2) , Jean-François Letard (2) , Eric Freysz (1)

1 CPMOH - Centre de physique moléculaire optique et hertzienne
2 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux

We show that the combination of a free running 80 MHz femtosecond Ti–sapphire oscillator with a nanosecond Nd:YAG laser makes it possible to record in real time, with a nanosecond time resolution, reversible or irreversible phase transitions photo-induced by a single laser pulse. This set-up is used to study the spin state transition photo-induced inside and outside the thermal hysteresis loops of a series of [Fe(NH₂trz)₃]X₂·nH₂O compounds (with X = NO₃ and Br). Original dynamics are presented and discussed. The results indicate that at room temperature, it is the laser induced heating that drives the recorded photo-induced phase transition.

Domaines: Matériaux

G. Gallé, Jérôme Degert, Cindy Mauriac, Céline Etrillard, Jean-François Letard, et al.. Nanoseconde study of spin state transition induced by a single nanosecond laser shot on [Fe(NH₂trz)₃] compounds inside and outside their thermal hysteresis loops. Chemical Physics Letters, 2010, 500 (1-3), pp.18-22. ⟨10.1016/j.cplett.2010.09.059⟩. ⟨hal-00549301⟩