Topological Surface States — Rashba Spin-Momentum Locking

Dirac cone surface states of a topological insulator with helical spin texture. Spin is locked perpendicular to momentum (Berry phase π), suppressing backscattering. Explore the Dirac cone, Fermi surface spin texture, and density of states.

Parameters

H_TI = v_F(k_x σ_y - k_y σ_x) + λk³cos(3θ)σ_z E_±(k) = ±v_F|k| (+ warping) Spin: ⟨σ_x⟩ = -sin(θ_k), ⟨σ_y⟩ = cos(θ_k) Berry phase: γ = π (Dirac fermion) No backscattering: ⟨k|T|-k⟩ = 0