Fig. 1.

(A) Crystal structure of bulk bismuth. The principle lattice vectors ${\overrightarrow{a}}_1=\left(\frac{-1}{2},\frac{-1}{2\sqrt{3}},\frac{1}{3}\right)$, ${\overrightarrow{a}}_2=\left(\frac{1}{2},\frac{-1}{2\sqrt{3}},\frac{1}{3}\right)$, and ${\overrightarrow{a}}_3=\left(0,\frac{1}{\sqrt{3}},\frac{1}{3}\right)$ are expressed in the Cartesian coordinates. (B) The bulk Brillouin zone. The principle reciprocal space vectors (${\overrightarrow{b}}_1$, ${\overrightarrow{b}}_2$, and ${\overrightarrow{b}}_3$) and high-symmetry points are noted. (C) Band structure of bismuth including spin–orbit coupling. The red and green circles represent positive and negative parity eigenvalues, respectively.