Photon Blockade — Jaynes-Cummings Model

In cavity QED, strong atom-photon coupling g creates anharmonic dressed states (polaritons). The energy spacing between |n⟩ and |n+1⟩ depends on √n, so a single photon blocks a second — photon blockade, producing antibunched light with g²(0) < 1.

Parameters

Coupling g/κ: 5.0 Drive Ω/κ: 0.5 Detuning Δ/κ: 0.00

g²(0) = —

H_JC = ωc a†a + ωa/2 σz + g(a†σ- + aσ+)
E_{n,±} = nω_c ± g√n (resonance)
Blockade: ΔE_1 = g√2-g ≠ ΔE_0
g²(0) = ⟨a†²a²⟩/⟨a†a⟩² < 1
Strong coupling: g ≫ κ, γ