Topological Surface States

Bulk-boundary correspondence & Dirac cone dispersion

Parameters

Surface states
Bulk valence
Bulk conduction
Bulk-boundary correspondence:
A topological insulator has gapped bulk bands but gapless surface states protected by time-reversal symmetry.

Dirac cone: E = ±ℏv_F|k| (massless when m→0)

Topological phase: m < 0 → Z₂ invariant ν=1
Trivial phase: m > 0 → ν=0

Drag mouse over cone to probe states.