Evolution of magnetoresistance with temperature in the insulating van der Waals compound Ta2Pd3Te5

Abstract

Ta2Pd3Te5 has been recently identified as a van der Waals topological crystalline insulator candidate, but its magnetotransport properties are not reported. Here, we study electrical transport properties of Ta2Pd3Te5 single crystals. Ta2Pd3Te5 shows an insulating behavior with a trend of saturation below 20 K. The activity energy determined from the fits to polaron hopping model is Ea ∼ 36.1 meV, close to the value of 42 meV determined from previous scanning tunneling microscopy measurement. The linear Hall resistivity with a negative slope suggests an n-type conductivity for bulk Ta2Pd3Te5. The magnetoresistance (MR) is positive at 2 K, and the dip-like feature at low magnetic fields is attributed to the weak antilocalization effect. On the other hand, a negative low-field MR develops in the temperature range between 5 and 30 K, which is identified as a fingerprint of the weak localization effect. Such a transition from weak antilocalization to weak localization with increasing temperature reveals that the spin–orbit interaction plays an important role in Ta2Pd3Te5. Our results reveal highly enriched physical properties in Ta2Pd3Te5 single crystals, and they can be exploited in future magnetoresistance device design.