Anisotropic thermal and electrical transport of Weyl semimetal TaAs. (9th November 2017)

• Record Type: Journal Article
• Authors: Xiang, Junsen; Hu, Sile; Lv, Meng; Zhang, Jiahao; Zhao, Hengcan; Chen, Genfu; Li, Wei; Chen, Ziyu; Sun, Peijie
• Is Part Of: Journal of physics. Volume 29:Number 48(2017)
• Publication Date: 2017-11-09
• Subjects: Weyl semimetal -- thermal transport -- thermoelectric power -- thermal conductivity; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/1361-648X/aa964b
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: We report on anisotropic electrical, thermal as well as thermoelectric properties of the prototypical Weyl semimetal TaAs. Compared to the normal metallic behavior along a axis, TaAs is more electrically resistive along c axis and exhibits a semiconductor-like resistivity upturn below T ≈ 25 K. In the same temperature range, the thermal conductivity along c axis shows a pronounced maximum of 183 W K m − 1 characteristic of a crystalline solid, three times higher than that of a axis. The thermoelectric power, while exhibiting enhanced values around room temperature, becomes diminished in a substantial range of temperature ( T < 50 K) for both axes. Together with the enhanced Nernst signals, this hints at a dominating ambipolar diffusion as is frequently seen in a compensated semimetal. An in-depth investigation of the anisotropic transport quantities is expected to yield deep insights into the propagating Weyl fermions in TaAs.