Fibonacci Quasiperiodic Chain — Tight-Binding Spectrum
Fibonacci quasicrystal — The chain is built by the substitution rule A→AB, B→A, producing lengths 1,1,2,3,5,8,13,… (Fibonacci numbers). Unlike periodic crystals, the spectrum is a Cantor set of measure zero in the thermodynamic limit — infinitely fragmented with self-similar gaps.
The tight-binding Hamiltonian Hij = Viδij + tijδ|i-j|,1 alternates hopping amplitudes tA/tB following the Fibonacci word. The integrated density of states (IDS) is a devil's staircase. The ratio tA/tB = φ (golden ratio ≈1.618) is the self-similar fixed point.
QuasicrystalCantor spectrumSelf-similarityTight-binding1D Schrödinger