Quantum oscillations in a topological insulator Bi2Te2Se with large bulk resistivity (image)

We report the observation of prominent Shubnikov–de Haas oscillations in a Topological Insulator, Bi2Te2Se, with large bulk resistivity (View the MathML source at 4 K). By fitting the SdH oscillations, we infer a large metallicity parameter kFℓ=41, with a surface mobility (View the MathML source) much larger than the bulk mobility (View the MathML source). The plot of the index fields Bν vs. filling factor ν shows a View the MathML source, consistent with massless, Dirac states.