论文标题
单轴应力对NBP电子带结构的影响
Effect of uniaxial stress on the electronic band structure of NbP
论文作者
论文摘要
Weyl Semimetal NBP表现出一个很小的费米表面，由两个电子和两个孔口袋组成，其在$ k $空间中的四倍变性与下面四方晶体晶格的旋转对称性相关。通过施加单轴应力，可以减少晶体对称性，从而导致费米 - 表面口袋的退化抬高。当磁场沿着四方晶格的$ c $轴对齐时，Shubnikov-de HAAS频率的分裂反映了这一点。在这项研究中，我们介绍了单轴张力下单晶NBP样品的shubnikov-de HAAS振荡，并结合了电子带结构的最新计算。我们的结果表明，计算出的和实验确定的shubnikov-de haas频率之间的定性一致性，证明了引入应变时的稳健性。此外，我们预测Weyl点会随着单轴张力的增加而显着转移，从而使有效的调整沿$ A $ A轴仅在0.8％的应变下，将其有效调整到费米水平。
The Weyl semimetal NbP exhibits a very small Fermi surface consisting of two electron and two hole pockets, whose fourfold degeneracy in $k$ space is tied to the rotational symmetry of the underlying tetragonal crystal lattice. By applying uniaxial stress, the crystal symmetry can be reduced, which successively leads to a degeneracy lifting of the Fermi-surface pockets. This is reflected by a splitting of the Shubnikov-de Haas frequencies when the magnetic field is aligned along the $c$ axis of the tetragonal lattice. In this study, we present the measurement of Shubnikov-de Haas oscillations of single-crystalline NbP samples under uniaxial tension, combined with state-of-the-art calculations of the electronic band structure. Our results show qualitative agreement between calculated and experimentally determined Shubnikov-de Haas frequencies, demonstrating the robustness of the band-structure calculations upon introducing strain. Furthermore, we predict a significant shift of the Weyl points with increasing uniaxial tension, allowing for an effective tuning to the Fermi level at only 0.8% of strain along the $a$ axis.
