Topological Dirac states in a layered telluride TaPdTe s with quasi-one-dimensional PdTe2 chains

Article

关键词: PHYSICAL-PROPERTIES;    SEMIMETAL;    MAGNETORESISTANCE;    DISCOVERY;    INSULATOR;    PHASE;   

DOI  :  10.1103/PhysRevB.102.075141

来源: SCIE

【 摘 要 】

We report the synthesis and systematic studies of a new layered ternary telluride TaPdTe5 with quasione-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 mu(h) = 2.38 x 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 x 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* (0.26m(e) and 0.41m(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.

【 授权许可】

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