Magnetic and thermoelectric properties of quasi-one-dimensional BaVSe3

Quasi-one-dimensional (Q1D) materials possess extraordinary magnetic and transport characteristics, which render them of critical importance. In this study, we present the synthesis of phase pure Q1D BaVSe ₃ via a novel heat treatment process and analyze its low-temperature thermoelectric, magnetotransport, and magnetic properties. A comparison is made between this phase pure system and the BaVSe ₃ infused with the secondary BaSe ₃ phase that we previously reported to determine the potential effect of impurities on the magnetic and thermoelectric properties. Our previous study covered the experimental and theoretical investigation on the exotic magnetic properties of BaVSe ₃ with BaSe ₃. In phase pure BaVSe ₃, at T _C ∼ 41.2 K, a paramagnetic to ferromagnetic transition with a magnetic moment of 1.74 μ _B from V ⁴⁺ was observed, consistent with calculated values. At very low temperatures (<117 K), the material behaved like glass, showed Griffiths-like behavior and spin valve-like butterfly magnetoresistance (BMR). Experiments indicate that these exotic magnetic properties are caused by the interaction between the A _1g and t _2g levels of the V 3d orbital and their spin orientation. Magnetic frustration in these materials is caused by V-V inter and intra chain interactions in the 1D spin chains of V. Q1D BaVSe ₃ (BVS) demonstrated n-type thermoelectricity with a thermoelectric figure of merit of ∼ 0.008, 4 × greater than BaVSe ₃:BaSe ₃ (BVS: BS) at room temperature. The thermal transport is determined to be primarily phonon-dependent. The magnetic property studies disclosed that this FM transition metal chalcogenide can contribute to low-temperature spintronics.