A 14 × 14 μm(2) footprint polarization-encoded quantum controlled-NOT gate based on hybrid waveguide

Area of Science:

• Quantum Information Science
• Integrated Photonics
• Quantum Computing Hardware

Background:

• Photonic quantum information processing is vital for communication, metrology, and lithography.
• Miniaturized photonic platforms are crucial for large-scale quantum information processing and computing.
• Existing integrated quantum logic gates primarily use path encoding, with polarization-encoded qubit technology underdeveloped.

Purpose of the Study:

• To implement a polarization-dependent beam-splitter in a hybrid waveguide system.
• To demonstrate a highly integrated, compact controlled-NOT gate for polarization-encoded qubits.
• To advance the development of large-scale quantum information processing systems and integrated photonic circuit capabilities.

Main Methods:

• Design and implementation of a polarization-dependent beam-splitter within a hybrid waveguide system.
• Utilizing the beam-splitter to construct a polarization-encoded controlled-NOT gate.
• Experimental demonstration of the integrated controlled-NOT gate functionality.

Main Results:

• Successful implementation of a polarization-dependent beam-splitter.
• Demonstration of a polarization-encoded controlled-NOT gate using a single such beam-splitter.
• Significant reduction in device footprint to 14 × 14 μm(2).
• Establishment of new capabilities for controlling polarization modes in integrated photonic circuits.

Conclusions:

• The developed polarization-dependent beam-splitter enables highly integrated controlled-NOT gates, crucial for scalable quantum information processing.
• This work significantly advances the development of miniaturized photonic platforms for quantum computing.
• The hybrid design offers novel functionalities for polarization mode control in integrated photonics.