The single-photon transmission spectrum under asymmetrical atom–photon couplings (g₁ = 0.2, g₂ = 0.15) and atom dissipation (1/T_a = 0.1 Ω): (a) Ω₁ = Ω₂ = Ω, 2θ = 2π (red line), 2θ = π (blue line), 2θ = 0.4π (green line); (b) Ω₁ = Ω₂ = Ω, 2θ = 2π (red line), 2θ = π (blue line), 2θ = 0.4π (green line)

Figure 5. The single-photon transmission spectrum under asymmetrical atom–photon couplings (g₁ = 0.2, g₂ = 0.15) and atom dissipation (1/T_a = 0.1 Ω): (a) Ω₁ = Ω₂ = Ω, 2θ = 2π (red line), 2θ = π (blue line), 2θ = 0.4π (green line); (b) Ω₁ = Ω₂ = Ω, 2θ = 2π (red line), 2θ = π (blue line), 2θ = 0.4π (green line). The coupling strengths g₁ and g₂ are in units of V_g.

Abstract

Based on the symmetric, asymmetric atom–photon couplings and the phase difference between two separated atoms, single-photon transport properties in an optical waveguide coupled with two separated two-level atoms are theoretically investigated. The transmission and reflection amplitudes for the single-photon propagation in such a hybrid system are deduced via a real-space approach. Several new phenomena such as phase-coupled induced transparency, single-photon switches, symmetric and asymmetric bifrequency photon attenuators are analyzed. In addition, the dissipation effect of such a hybrid system is also discussed.