High field Fermi surfaces studied by AMRO in η-Mo 4O 11

Abstract

The high field Fermi surface in η-Mo 4O 11 at low temperatures has been studied by the Angle-dependent Magnetoresistance Oscillation (AMRO) method (Organic Super Conductors, Springer, Berlin, 1998, p. 455). The Shubnikov–de Haas (SdH) oscillation so far obtained shows existence of the several closed surfaces, but the results only give the area of the pockets. The AMRO result at high fields in the plane perpendicular to the crystal b-axis shows the angle-dependent resistance oscillation together with the SdH oscillations. We see no clear AMRO for the fields in the plane perpendicular to the c-axis. The results indicate the existence of very anisotropic Fermi surfaces, which are expected from the Fermi surface model (Chem. Rev. 91 (1991) 965) taking into account the lower temperature CDW nesting vector q 2.