Magnetic and thermoelectric properties of quasi-one-dimensional BaVSe3

Abstract

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 BaVSe3 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 BaVSe3 infused with the secondary BaSe3 phase that we previously reported todetermine 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 BaVSe3 with BaSe3. In phase pure BaVSe3, at TC ∼ 41.2 K, a paramagnetic to ferromagnetic transition with a magnetic moment of 1.74 μB from V4+ was observed,consistent with calculated values. At very low temperatures (<117 K), the material behaved like glass, showed Griffiths-like behaviorand spin valve-like butterfly magnetoresistance (BMR). Experiments indicate that these exotic magnetic properties are caused by the interaction between the A1g and t2g 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 BaVSe3 (BVS) demonstrated n-type thermoelectricity with a thermoelectric figure of merit of ∼ 0.008, 4 × greater than BaVSe3:BaSe3 (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.