Fermi Surface of Bi(111) Measured by Photoemission Spectroscopy

Synchrotron radiation angle-resolved photoemission spectroscopy of Bi(111) shows that the Fermi surface consists of six elongated hole pockets along the $\overline{\Gamma M}$ directions surrounding a ring-shaped electron pocket centered at $\overline{\Gamma }$, all of which have two-dimensional character. The associated hole and electron sheet densities are $p_s=1.1\mathrm{}\times {10}^{13}{\mathrm{cm}}^{-2\mathrm{}}$ and $n_s=5.5\mathrm{}\times {10}^{12}{\mathrm{cm}}^{-2\mathrm{}}$, respectively. A weak emission feature associated with the bulk hole pocket in the Fermi surface was identified. The Fermi momentum of the bulk hole band near the $T$ point is $k_F=0.013\mathrm{}\pm 0.003{\AA }^{-1\mathrm{}}$.