Universal photon blockades via parametric amplification in second-order nonlinearly coupled cavities

Area of Science:

• Quantum optics
• Nonlinear optics
• Cavity quantum electrodynamics

Background:

• Photon blockade (PB) is crucial for single-photon sources, with conventional and unconventional types.
• Bridging these regimes offers enhanced control and performance.
• Existing schemes often face limitations in coupling regimes or experimental constraints.

Purpose of the Study:

• To propose and analyze a scheme for universal photon blockade (universal PB).
• To combine the advantages of conventional and unconventional photon blockade.
• To provide a tunable platform for high-purity single-photon generation.

Main Methods:

• Utilizing second-order nonlinearity for inter-cavity mode coupling.
• Incorporating an optical parametric amplifier for quantum interference.
• Analytical derivation of optimal conditions for universal PB.
• Numerical simulations to validate analytical findings.

Main Results:

• Achieved universal PB by mediating interaction via second-order nonlinear coupling.
• Demonstrated effective operation in both strong and weak coupling regimes.
• Obtained an ultra-low equal-time second-order correlation function (g(2)(0)) down to 10⁻⁷.
• Maintained a moderate mean photon number (N_a ~ 10⁻²).

Conclusions:

• The proposed scheme offers a feasible and tunable platform for universal PB.
• It overcomes limitations of conventional PB, relaxing experimental constraints.
• Enables the generation of high-purity single-photon sources and exploration of quantum statistics.