Reconfigurable free-space mode generation and detection enabled by an active photonic integrated circuit coupled to a...

Area of Science:

• Photonics and Optical Engineering
• Quantum Technologies
• Integrated Optics

Background:

• Optical mode manipulation is crucial for quantum, sensing, and communication technologies.
• Existing photonic systems struggle with real-time adaptation to changing conditions.
• Phased arrays on photonic integrated circuits (PICs) offer high-speed reconfiguration but face limitations like the Nyquist-sampling limit.

Purpose of the Study:

• To develop a high-speed, reconfigurable optical mode-sorting and generation system.
• To overcome the limitations of traditional phased-array systems in photonic integrated circuits.
• To enable real-time adaptation of photonic systems for advanced applications.

Main Methods:

• Utilized a passive Multiple-Plane-Light-Converters (MPLC) as an Optical Mode-Selective Interface (OMSI).
• Coupled free-space Hermite Gaussian (HG) modes into an active optical mesh on a PIC.
• Demonstrated generation and sorting of orthogonal mode groups via linear superposition.

Main Results:

• Successfully generated and sorted four orthogonal mode groups, each containing 15 HG modes.
• Achieved a mean intermodal crosstalk of -22 dB for mode sorting.
• Showcased a reconfigurable system without physical modification.

Conclusions:

• The developed Optical Mode-Selective Interface (OMSI) enables rapid, high-fidelity optical mode manipulation.
• This technology facilitates the creation of fast, reconfigurable mode-sorters for quantum communications, classical communications, and sensing.
• The approach overcomes limitations of existing technologies, paving the way for next-generation photonic systems.