| Numéro |
J. Phys. IV France
Volume 114, April 2004
|
|
|---|---|---|
| Page(s) | 111 - 112 | |
| DOI | https://doi.org/10.1051/jp4:2004114022 | |
J. Phys. IV France 114 (2004) 111
DOI: 10.1051/jp4:2004114022
Anomalous thermal expansion behavior in (TMTTF) 2PF 6 and (TMTSF) 2PF 6 around 100 K: Indications for a strong spin-phonon interaction?
M. Lang1, J. Müller2, F. Steglich2, A. Brühl1, B. Wolf1 and M. Dressel31 Institute of Physics, J.W. Goethe-University Frankfurt, 60054 Frankfurt (M), Germany
2 Max-Planck-Institut for Chemical Physics of Solids, 01187 Dresden, Germany
3 Institute of Physics I, University of Stuttgart, 70550 Stuttgart, Germany
Abstract
High-resolution measurements of the coefficient of
thermal expansion along the b axis,
, on the quasi-1D
Spin-Peierls and spin-density-wave systems (TMTTF)
2PF
6 and
(TMTSF)
2PF
6, respectively, reveal an anomalous
(T)
contribution around 100 K. This feature, which is most strongly pronounced
in the SP system, is reminiscent of the magnetic contribution observed in
low-dimensional spin systems with a strong spin-lattice interaction such as
CuGeO
3. Remarkably enough, the position of the
anomalies for both compounds almost coincide with the temperatures where the
thermal conductivity shows a distinct minimum [T. Lorenz et al., Nature
418 (2002) 614]. Our observation indicates a significant role of
the spin-lattice interaction for these systems.
Key words. Spin - phonon interaction, thermodynamic properties.
© EDP Sciences 2004