J. Phys. IV France
Volume 12, Numéro 9, November 2002
Page(s) 23 - 26

J. Phys. IV France
12 (2002) Pr9-23
DOI: 10.1051/jp4:20020346

Low temperature heterogeneous dynamics in the commensurate ground state of sulfur quasi4 D compounds (TMTTF) 2Br and (TMTTF) 2PF 6

J.C. Lasjaunias1, K. Biljakovic2, D. Staresinic2 and P. Monceau1

1  Centre de Recherches sur les Très Basses Températures, CNRS, BP. 766, 38042 Grenoble cedex 9, France
2  Institute of Physics, P.O. Box 304, 70001 Zagreb, Croatia

We report on a study of the slow dynamics of the heat relaxation at very low temperature (T $\leq$1 K) in the nominally commensurate ground states of the sulfide compounds (TMTTF) 2Br and (TMTTF) 2PF 6, commensurate SDW - or antifernomagnetic - and spin-Peierls, respectively. For both systems, the long-time dynamics at equilibrium shows a bimodal character, which can be analysed by slow and fast gaussian distributions $g(\log\tau )$, separated by one decade in time, which can originate from defects of commensurability.

© EDP Sciences 2002