论文标题
拓扑狄拉克态在分层的telluride tapdte中
Topological Dirac states in a layered telluride TaPdTe$_5$ with quasi-one-dimensional PdTe$_2$ chains
论文作者
论文摘要
我们报告了具有准二维PDTE2链的新分层三元triberide tapdte5的合成和系统研究。该复合在分层的正交结构中与空间组CMCM结晶。使用两波段模型对其曲面依赖场的霍尔电阻率进行分析，表明具有高移动性$μ_H$ = 2.38 $ = 2.38 $ \ times $ 10 $^3 $^3 $ cm $^2 $ v $^2 $ v $^{ - 1} $ s $ s $^{ - 1} $在低温下。面内磁阻（MR）显示出明显的各向异性，沿晶体学$ B $轴施加了场。在高达51.7 t的高磁场上还测量了沿着$ c $轴施加的电流的MR。值得注意的是，它遵循2.1 K的幂律依赖并达到（9.5 $ \ times $ 10 $^3 $）％，而没有任何饱和的标志。 de haas-van alphen振荡显示一个小的费米表面袋，具有非平凡的浆果相。从低温下，在28.5吨以上的磁场下检测到Shubnikov-de Haas（SDH）振荡。从振动性SDH数据中提取了两个有效的质量$ m^*$（0.26 $ m_e $和0.41 $ m_e $）。我们的第一原理计算在其表面状态下揭示了拓扑狄拉克锥，尤其是拓扑指数表明Tapdte $ _5 $是拓扑上的非平凡材料。
We report the synthesis and systematic studies of a new layered ternary telluride TaPdTe5 with quasi-one-dimensional PdTe2 chains. This compound crystalizes in a layered orthorhombic structure with space group Cmcm. Analysis of its curved field-dependent Hall resistivity, using the two-band model, indicates the hole-dominated transport with a high mobility $μ_h$ = 2.38 $\times$ 10$^3$ cm$^2$ V$^{-1}$ s$^{-1}$ at low temperatures. The in-plane magnetoresistance (MR) displays significant anisotropy with field applied along the crystallographic $b$ axis. The MR with the current applied along the $c$-axis is also measured in high magnetic fields up to 51.7 T. Remarkably, it follows a power-law dependence and reaches (9.5 $\times$ 10$^3$)% at 2.1 K without any signature of saturation. The De Haas-van Alphen oscillations show a small Fermi-surface pocket with a nontrivial Berry phase. The Shubnikov-de Haas (SdH) oscillations are detected at low temperatures and under magnetic fields above 28.5 T. Two effective masses $m^*$ (0.26$m_e$ and 0.41$m_e$) are extracted from the oscillatory SdH data. Our first-principles calculations unveil a topological Dirac cone in its surface states, and, in particular, the topological index indicates that TaPdTe$_5$ is a topologically nontrivial material.
