Transport properties and the large anisotropic magnetoresistance of CuxNbS2 single crystals

The transport properties of CuxNbS2 (x = 0.09, 0.44 and 0.55) single crystals were systematically studied. The in-plane and out-of-plane resistivities decrease with increasing Cu content, and a transition with hysteresis shows up for the crystals with x = 0.44 and 0.55. The thermopower and Hall coefficient of CuxNbS2 show opposite signs, indicating that there are two kinds of carriers in this system. The angular dependences of the in-plane magnetoresistance (MRab = (rho(ab)(H) - rho(ab)(0))/rho(ab)(0) x 100%) at different temperatures were also studied. The single crystals with x = 0.44 and 0.55 show a strong anisotropic MRab. For the x = 0.55 sample, MRab reaches 80% with a magnetic field of 14 T applied along the c-axis, while MRab is less than 5% for the magnetic field applied within the ab-plane. These results can be well understood in the light of the anisotropic Fermi surface in the multiband system.