Anomalous Angular Dependence of Magnetoresistance of an Organic Superconductor, (DMET)₂I₃

Abstract

Angular dependence of magnetoresistance of a quasi-one-dimensional organic superconductor, (DMET) 2 I 3 has been measured at 4.2 K for magnetic fields up to 7.0 T. For the field of 1.0 T, the angular dependence of the magnetoresistance is smooth over the entire range of angles, reflecting the quasi-one-dimensional band structure of the salt. When the magnetic field of 7.0 T was rotated in the most conducting a b plane, the magnetoresistance for the current along both the b- and c * -axes showed discontinuous changes in its slope at the angles of ±15° from the most conducting axis. The anomaly occurring at 7.0 T is considered to be due to a change in electronic state induced by the magnetic field almost perpendicular to the quasi-1D Fermi surface.