We have studied the magnetic, transport and structural properties of chalcogenide spinel compound CuV2S4 using a high-quality polycrystalline sample, in order to clarify the intrinsic physical properties of CuV2S4. The magnetic susceptibility and the electrical resistivity exhibit two sharp anomalies. One is reversible for temperature Tt1 = 91.5 K and the other shows a thermal hysteresis of about 4 K at Tt2 = 56 K. We clearly observed for the first time that both anomalies are accompanied with two-step structural modulations. The crystal structure changes the symmetry form cubic to tetragonal at Tt1, and then the lattice constant is modulated discontinuously at Tt2 without changing the symmetry. In addition, the paramagnetic susceptibility is very large, and the electrical resistivity at low temperatures shows a quadratic temperature dependence with the coefficient A = 0.05 μΩ cm/K 2, which is larger than that of conventional metals. These results indicate that CuV2S4 exhibits a Fermi-liquid-like behavior with strongly correlated electrons at lower temperatures.
- Charge density wave
- Strongly correlated electron system
- Structural phase transition
ASJC Scopus subject areas
- Physics and Astronomy(all)