Fermi surface of the Weyl type-II metallic candidate WP 2
Fermi surface of the Weyl type-II metallic candidate WP 2
复制标题
DOI：
10.1103/physrevb.96.121108
复制
发表时间：
2017-06
期刊：
影响因子：
--
通讯作者：
R. Schonemann;N. Aryal;Q. Zhou;Y. Chiu;K. Chen;T. J. Martin;G. McCandless;J. Chan;E. Manousak
中科院分区：
文献类型：
--
作者：
R. Schonemann;N. Aryal;Q. Zhou;Y. Chiu;K. Chen;T. J. Martin;G. McCandless;J. Chan;E. Manousak
Weyl-II类费米子是遵循Weyl方程的无质量准粒子，预计会出现在某些半金属中的电子和空穴之间的边界上，即(W，Mo)(Te，P)$2$化合物。在这里，我们通过Shubnikov-de Haas(SDH)效应研究了WP$2的费米面。与其他半金属相比，WP$2具有很低的剩余电阻率，即$Rho_0\Simeq 10$n$\Omega$cm，这可能是已报道的化合物中最大的非饱和磁阻率$(Rho(H))。当T=0.35$K时，当H=35$T时，当H=35$T时，当电子和空穴能带相对于费米能级略有移动时，SDH频率的角度依赖关系与第一性原理计算很好地符合，从而支持WP$2$中潜在Weyl II型点的存在。
Weyl type-II fermions are massless quasiparticles that obey the Weyl equation and which are predicted to occur at the boundary between electron- and hole-pockets in certain semi-metals, i.e. the (W,Mo)(Te,P)$_2$ compounds. Here, we present a study of the Fermi-surface of WP$_2$ \emph{via} the Shubnikov-de Haas (SdH) effect. Compared to other semi-metals WP$_2$ exhibits a very low residual resistivity, i.e. $\rho_0 \simeq 10$ n$\Omega$cm, which leads to perhaps the largest non-saturating magneto-resistivity $(\rho(H))$ reported for any compound. For the samples displaying the smallest $\rho_0$, $\rho(H)$ is observed to increase by a factor of $2.5 \times 10^{7}$ $\%$ under $\mu_{0}H = 35$ T at $T = 0.35$ K. The angular dependence of the SdH frequencies is found to be in very good agreement with the first-principle calculations when the electron- and hole-bands are slightly shifted with respect to the Fermi level, thus supporting the existence of underlying Weyl type-II points in WP$_2$.