Dynamical separation of spin and lattice degrees of freedom in the relaxation process from the photo-induced state

H. Watanabe (1, 2) , Nicolas Bréfuel (3, 4) , Shin-Ichiro Mouri (5) , Jean-Pierre Tuchagues (4) , Eric Collet (1) , K. Tanaka (2, 5)

1 IPR - Institut de Physique de Rennes
2 Kyoto University
3 LNCMI-G - Laboratoire national des champs magnétiques intenses - Grenoble
4 LCC - Laboratoire de chimie de coordination
5 Institute for Integrated Cell-Material Sciences

We have studied the relaxation dynamics from the photo-induced state in the spin crossover complex [FeH2L2-Me](ClO4)2 by magnetic susceptibility and X-ray diffraction measurements. Just after turning off the laser irradiation, the photo-induced high-spin state immediately starts relaxing back to the low-spin state, while the crystal lattice shows a nucleation process. This result shows that the spin state and lattice deformation should be treated as individual parameters in the non-equilibrium phase transition from the photo-induced state. Experimental results are qualitatively explained by the two-sublattice Ising-like model.

Mots clés: Condensed matter: electrical; magnetic and optical; Condensed matter: structural; mechanical & thermal; Statistical physics and nonlinear systems

Domaines: Physique : vulgarisation [physics.pop-ph]

H. Watanabe, Nicolas Bréfuel, Shin-Ichiro Mouri, Jean-Pierre Tuchagues, Eric Collet, et al.. Dynamical separation of spin and lattice degrees of freedom in the relaxation process from the photo-induced state. EPL - Europhysics Letters, 2011, 96, pp.17004. ⟨10.1209/0295-5075/96/17004⟩. ⟨hal-00697449⟩