Fano Resonance — Coupled Oscillator

PARAMETERS

Discrete level ω₀ 1.00 Coupling q (Fano) 2.00 Damping Γ 0.10 Continuum width Δ 0.30 Drive frequency ω 0.80

FANO FORMULA

σ(E) ∝ (q + ε)² / (1 + ε²)
ε = (E − E₀) / (Γ/2)
q = Fano asymmetry parameter

Asymmetric lineshape from interference between discrete resonance and continuum. q→∞: Lorentzian; q=0: anti-resonance dip; intermediate q: asymmetric Fano profile.