Quasiparticle DOS — coherence peaks at ±Δ
BCS gap Δ(T) vs temperature
Cooper pair formation — electrons near Fermi surface attracted via phonon exchange
Δ(T=0) ≈ 1.764 k_B T_c
N(E) = N₀|E|/√(E²−Δ²) for |E|>Δ
1 = VN₀ ln(2ωD/Δ)
N(E) = N₀|E|/√(E²−Δ²) for |E|>Δ
1 = VN₀ ln(2ωD/Δ)
The BCS gap Δ vanishes at T=Tc (second-order phase transition). Coherence peaks in DOS are key signatures in tunneling spectroscopy.