Figure 3

Raman spectrum of a single nanowire and representation of the Raman data for Bi ₂ (Te _1−xSe _x ) ₃ . (a) Raman spectrum of a nanowire grown at 480°C. Four peaks at 66, 112, 129, and 164 cm ⁻¹ are obtained from fitting Lorentzians. The peaks can be assigned to the Raman modes of Bi₂Se₂Te. (b) Representation of the Raman data for Bi₂(Te _1−xSe _x )₃ for 0<x<1 taken from Richter and Becker [21]. Data points of the higher A${}_{1g}^2$ and the E${}_g^2$ mode were fitted with a spline interpolation. Red dashed lines indicate the peak positions of the nanowire and the shaded grey area the composition range of x≈0.69±0.02.