Magnetic impurity density of states — Kondo peak at Fermi level below T_K
T_K = — | Kondo peak height: — | Regime: —
The Kondo effect arises when a magnetic impurity (spin-½) couples to conduction electrons via exchange J.
Below the Kondo temperature T_K ∝ exp(−1/2Jρ₀), a many-body resonance forms at the Fermi energy ω=0.
The impurity spectral function A(ω) shows: (1) a broad charge-fluctuation peak near ε_d,
(2) a narrow Kondo peak at ω=0 with width ~ T_K. At T ≫ T_K the Kondo peak disappears.