Eur. Phys. J. B 31, 53-61 (2003)
https://doi.org/10.1140/epjb/e2003-00008-8

Magnetic oscillations in the 2D network of compensated coupled orbits of the organic metal (BEDT-TTF)₈Hg₄Cl₁₂(C₆H₅Br)₂

¹ Laboratoire de Physique de la Matière Condensée (UMR 5830: Unité Mixte de Recherche CNRS – Université Paul Sabatier – INSA de Toulouse) , 135 avenue de Rangueil, 31077 Toulouse, France
² Laboratoire National des Champs Magnétiques Pulsés (UMS 5642: Unité Mixte de Service CNRS – Université Paul Sabatier – INSA de Toulouse) , 143 avenue de Rangueil, 31432 Toulouse, France
³ Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka 142432, Russia

Corresponding author: ^a audouard@insa-tlse.fr

Received: 4 September 2002
Revised: 14 November 2002
Published online: 27 January 2003

Abstract

Interlayer magnetoresistance and magnetisation of the quasi-two dimensional organic metal (BEDT-TTF)₈Hg₄Cl₁₂(C₆H₅Br)₂ have been investigated in pulsed magnetic fields extending up to 60 T and 33 T, respectively. About fifteen fundamental frequencies, composed of linear combinations of only three basic frequencies, are observed in the oscillatory spectra of the magnetoresistance. The dependencies of the oscillation amplitude on the temperature and on the magnitude and orientation of the magnetic field are analyzed in the framework of the conventional two-dimensional Lifshitz-Kosevitch (LK) model. This model is implemented by damping factors which accounts for the magnetic breakthrough occurring between electron and hole orbits yielding conventional Shubnikov-de Haas closed orbits (model of Falicov and Stachowiak) and quantum interferometers. In particular, a quantum interferometer enclosing an area equal to the first Brillouin zone area is evidenced. The LK model consistently accounts for the temperature and magnetic field dependence of the oscillation amplitude of this interferometer. On the contrary, although this model formally accounts for almost all of the observed oscillatory components, it fails to give consistent quantitative data in most other cases.