Shubnikov-de Haas effects in Bi2Se3 with high carrier concentrations☆

Abstract Shubnikov-de Haas frequencies were measured in highly degenerate n -type Bi 2 Se 3 having a higher carrier density (∼9 × 10 25 m -3 ) than previously reported. The Fermi surface was found to be elongated along the trigonal axis, fitting a spheroidal model with an axial ratio of 5.0 for angles up to θ = 45°. Comparison of the number of carriers obtained from Hall measurements with that obtained from the Shubnikov-de Haas measurement supports the contention that the lowest conduction band minimum is a single surface located in the center of the Brillouin zone. The higher effective mass (0.25 m 0 ) found for these carrier concentrations indicates that the band is non-parabolic.