Tunable arbitrary unitary transformer based on multiple sections of multicore fibers with phase control

Area of Science:

• Photonics and Optical Communications
• Quantum Information Processing

Background:

• Unitary transforms are fundamental in signal processing and quantum computing.
• Existing methods for implementing unitary transforms can be complex and lack tunability.

Purpose of the Study:

• To propose a novel tunable unitary transformer capable of arbitrary discrete unitary transforms.
• To demonstrate its application in mode division multiplexing systems.

Main Methods:

• The transformer utilizes multi-core fibers with closely aligned coupled cores.
• Phase shifters are integrated to control wave phases, enabling precise unitary operations.
• A simple algorithm optimizes phase shifter settings for desired transforms.

Main Results:

• The proposed device successfully achieves arbitrary discrete unitary transforms.
• A tunable mode multiplexer/demultiplexer (MUX/DEMUX) for a three-mode fiber was designed.
• The fiber-based nature ensures suitability for integrated photonic applications.

Conclusions:

• The novel tunable unitary transformer offers a flexible and efficient approach to implementing unitary operations.
• This technology has significant potential for advancing mode division multiplexing and related photonic systems.