Entangled photon generation using four-wave mixing in azimuthally symmetric microresonators

Area of Science:

• Quantum mechanics
• Quantum optics
• Photonics

Background:

• Four-wave mixing (FWM) is a key nonlinear optical process for generating entangled photons.
• Traditional FWM analysis often relies on linear group velocity, which may not fully capture behavior in complex systems.
• Understanding bi-photon wavefunctions is crucial for advancements in quantum information science.

Purpose of the Study:

• To develop a novel quantum mechanical formulation for bi-photon wavefunctions and spectra in azimuthally symmetric systems undergoing four-wave mixing.
• To investigate the role of angular group velocity and dispersion in these systems.
• To propose a scheme for generating widely spaced narrowband entangled photons using chip-scale resonators.

Main Methods:

• Developed a new quantum mechanical framework for describing bi-photon states in FWM.
• Performed numerical calculations to analyze the system's dispersion profile and bi-photon spectra.
• Utilized angular group velocity and angular group velocity dispersion in the theoretical formulation.

Main Results:

• Verified the applicability of angular group velocity and dispersion in azimuthally symmetric FWM systems.
• Illustrated the physical origins of energy and momentum conservation in bi-photon generation.
• Demonstrated a scheme for producing entangled photon pairs with wide spectral separation in a ring resonator.

Conclusions:

• The novel quantum mechanical formulation accurately describes bi-photon properties in FWM.
• Angular group velocity is a critical parameter for understanding and controlling entangled photon generation in these systems.
• The proposed chip-scale resonator scheme offers a promising route for practical applications in quantum communication and computing.