t₁ = 1.00
t₂ = 0.40
t₂/t₁ = 0.40
Winding number W = 1
Phase: Topological
About: The SSH model is the simplest 1D topological insulator. A chain of 2N sites has alternating hopping amplitudes t₁ (intra-cell) and t₂ (inter-cell). When t₂/t₁ < 1, the system is in a topological phase with winding number W=1 and protected zero-energy edge states localized at the chain ends. When t₂/t₁ > 1, W=0 and no edge states exist. This bulk-boundary correspondence is a hallmark of topological phases of matter.