Europhys. Lett.
Volume 67, Number 6, September 2004
Page(s) 1024 - 1030
Section Condensed matter: electronic structure, electrical, magnetic, and optical properties
Published online 01 September 2004
Europhys. Lett., 67 (6), pp. 1024-1030 (2004)
DOI: 10.1209/epl/i2004-10152-3

Unconventional spin density wave in Bechgaard salt $\chem{(TMTSF)_2PF_6}$

B. Dóra1, K. Maki2, A. Ványolos3 and A. Virosztek3, 4

1  The Abdus Salam ICTP - Strada Costiera 11, Trieste, I-34014, Italy
2  Department of Physics and Astronomy, University of Southern California Los Angeles CA 90089-0484, USA
3  Department of Physics, Budapest University of Technology and Economics H-1521 Budapest, Hungary
4  Research Institute for Solid State Physics and Optics P.O. Box 49, H-1525 Budapest, Hungary

(Received 27 May 2004; accepted in final form 19 July 2004)

The quasi-one-dimensional organic conductor Bechgaard salts $\chem{(TMTSF)_2}$X with $\chem{X}=\chem{PF_6}$, $\chem{ClO_4}$, $\chem{AsF_6}$, etc. are well known for the variety of their ground states: spin density wave (SDW), field-induced spin density wave (FISDW) and triplet superconductivity. We propose here that the unconventional spin density wave (USDW) occupies a large area of the P- B phase diagram, where SDW is suppressed by pressure ( P) and superconductivity by magnetic field ( B) and FISDW is still absent. USDW describes the striking angular dependent magnetoresistance (ADMR) seen in this area of the phase diagram, when the magnetic field is rotated in the c*- $b^{\prime}$ plane. Also the Lebed resonances are naturally interpreted in terms of the imperfect nesting term.

75.30.Fv - Spin-density waves.
71.45.Lr - Charge-density-wave systems.
72.15.Eb - Electrical and thermal conduction in crystalline metals and alloys.

© EDP Sciences 2004