Observation of large in-plane anisotropic transport in van derWaals semiconductor Nb2SiTe4 * *Project supported by the National Key Research and Development Program of China (Grant Nos. 2018YFE0202600, 2016YFA0300600, and 2017YFA0304700), by the National Natural Science Foundation of China (Grant Nos. 51922105, 51772322, and 11704401), and Beijing Natural Science Foundation (Grant No. Z200005).

Abstract

Two-dimensional (2D) van der Waals material is a focus of research for its widespread application in optoelectronics, memories, and spintronics. The ternary compound Nb2SiTe4 is a van der Waals semiconductor with excellent air stability and small cleavage energy, which is suitable for preparing a few layers counterpart to explore novel properties. Here, properties of bulk Nb2SiTe4 with large in-plane electrical anisotropy are demonstrated. It is found that hole carriers dominate at a temperature above 45 K with a carrier active energy of 31.3 meV. The carrier mobility measured at 100 K is about 213 cm2⋅V−1⋅s−1 in bulk Nb2SiTe4, higher than the reported results. In a thin flake Nb2SiTe4, the resistivity ratio between the crystalline axes of a and b is reaching about 47.3 at 2.5 K, indicating that there exists a large anisotropic transport behavior in their basal plane. These novel transport properties provide accurate information for modulating or utilizing Nb2SiTe4 for electronic device applications.