DFT of (Bi 1− x Sb x ) 2 Te 3 and (Bi 1− x Sb x ) 2 Se 3 (0 ≤ x ≤ 1) shows Sn tunes structure, band inversion, spin texture, and transport. In Bi 2 Te 3 a pronounced Rashba splitting appears at x = 0.6 with α R = 2.098 eV Å.
Kavkhani et al. (Thu,) studied this question.