第二类狄拉克半金属NiTe2的合成及其物理性质研究

Synthesis and Physical Properties of Type-Ⅱ Dirac Semimetal NiTe2

主要介绍了第二类狄拉克半金属NiTe2的合成和传输性质研究.发现NiTe2在低温(T=2 K)、强磁场下(B=9 T)的磁电阻达1 300%.另外,其电阻率-温度曲线在低温下表现出磁场诱导的金属绝缘体转变.进一步的霍尔效应测量发现NiTe2在低温下表现出双带行为.这些物理性质都表明NiTe2很可能是一种新型的第二类狄拉克半金属材料.因此,该材料为拓扑材料物性研究和新型拓扑材料的发现提供了新的载体与依据.

This paper mainly reports the synthesis and the thermodynamic properties of a new type-II Dirac semimetal candidate NiTe2. It is found that the magnetoresistance of NiTe2 reaches a magnitude of as high as 1 300% at a low temperature(T=2 K) and high magnetic field(B=9 T). In addition, the field-induced metalinsulator transition is also observed on its temperature-dependent resistivity curves in this compound. The further Hall measurements reveal the two-band carriers at low temperatures. All these properties suggest that NiTe2 may be a new type-II Dirac semimetal, which can provide a platform for investigating the physical properties of topological materials, and more importantly, a basis for discovering a new class of topological materials.