The g‐factor of the conduction electrons in Bi2Se3

The oscillatory part of the magneto‐resistance (Shubnikov‐de Haas effect) was investigated on n‐Bi2Se3 single crystals with carrier concentrations between 5 × 1017 and 1 × 1018cm−3 in the temperature range from 1.6 to 4.2 K in pulsed magnetic fields up to 35 T (350 kG) magnetic induction. Most experiments were performed for the magnetic induction B parallel to the trigonal axis c of the crystals, where the smallest cyclotron mass mc and a parabolic ε(κ) relation is present. No spin‐splitting of the Shubnikov‐de Haas resistivity extrema is observed at high quantum numbers. At low quantum numbers the influence of spin‐splitting causes a shift of the resistivity extrema and an additional maximum, which should not be present for M = gmc/(2m0) ≪ 1. A calculation of the magnetoresistance in quantizing magnetic fields based on Kubo's theory for a field‐independent carrier concentration enables the determination of the expression M = gmc/(2m0) = 2 with ±5% uncertainty for B‖ c. The absolute value of the g‐factor is evaluated hence as (32 ± 3) for B‖ c. For arbitrary crystal orientation in the magnetic field M may be assumed to be constant within the error margin, the g‐factor being consequently smaller for B ⟂ c: g ⟂ = (23 ± 3).