Cascaded optical resonator-based programmable photonic integrated circuits.

Area of Science:

• Photonics
• Integrated Optics
• Quantum Information

Background:

• Programmable photonic integrated circuits (PICs) traditionally rely on Mach-Zehnder interferometers (MZIs).
• MZIs typically operate on a single wavelength channel, limiting functionality and increasing footprint.
• Tunable phase shifters are key components in current MZI-based PICs.

Purpose of the Study:

• To propose and investigate novel optical circuit models for PICs.
• To enable independent operation of multiple wavelength channels within a compact device.
• To explore resonator-based designs as an alternative to MZIs.

Main Methods:

• Developing optical circuit models based on cascaded optical resonators.
• Utilizing experimental data from silicon micro-ring resonators.
• Applying the Reck and Clements algorithms to evaluate transformation fidelities.
• Examining 2x2 and higher-dimensional unitary transformations.

Main Results:

• Demonstrated that cascaded optical resonators can achieve independent multi-wavelength channel operation.
• Achieved a more compact footprint compared to conventional MZI-based designs.
• Quantified the fidelities of various unitary transformations using resonator circuits.

Conclusions:

• Cascaded optical resonators offer a promising, compact alternative for programmable photonic integrated circuits.
• This approach facilitates independent control over multiple wavelength channels.
• The proposed models show high fidelity for implementing complex optical transformations.