Coexistence of one- and three-dimensional Fermi surfaces and heavy cyclotron mass in the molecular conductor (DMe-DCNQI)2Cu

The Fermi surface of the molecular conductor (DMe-DCNQI)2Cu (DMe-DCNQI=2,5-dimethyl-N,N-dicyanoquinonediimine) has been investigated by the de Haas van Alphen method. Seven different oscillations with heavy cyclotron masses are observed at frequencies lower than 3000 T. These effects arise from the three-dimensional (3D) Fermi surface which is dominated mainly by the Cu 3d orbital character. Many oscillations with frequency higher than 3000 T are detected for the magnetic field in the ab plane an effect which demonstrates the coexistence of the 1D and 3D Fermi surfaces.