J. Phys. I France
Volume 3, Numéro 5, May 1993
Page(s) 1187 - 1199
DOI: 10.1051/jp1:1993264
J. Phys. I France 3 (1993) 1187-1199

Magnetotransport investigation of the low-temperature state of transition (BEDT-TTF) $_{\rm {2}}$TIHg(SCN) $_{\rm {4}}$ : evidence for a Peierls-type transition

M. V. Kartsovnik1, A. E. Kovalev1 and N. D. Kushch2

1  Institute of Solid State Physics, Russian Academy of Sciences, 142432, Chemogolovka, MD, Russia
2  Jnstitute of Chemical Physics in Chemogolovka, Russian Academy of Sciences, 142432, Chemogolovka, MD, Russia

(Received 22 December 1992, accepted 26 January 1993)

Detailed magnetoresistance measurements have been performed on (BEDT-TTF) $_{\rm {2}}$TlHg(SCN) $_{\rm {4}}$. An analysis of angle dependent semi-classical magnetoresistance oscillations is presented in connection with possible changes in the electron spectrum at low temperatures. A spin density wave is proposed to arise leading to a modification of the Fermi surface so that new open sheets appear, consistent with the observed angular magnetoresistance oscillations. Some details of the Shubnikov-de Haas effect are also presented which can be explained by the existence of a magnetic breakdown network, in agreement with the proposed low- temperature electronic state of the compound.

72.15G - 73.201 - 74.70K

© Les Editions de Physique 1993