Observation of Hong-Ou-Mandel interference with scalable Yb⁺-photon interfaces

Area of Science:

• Quantum Information Science
• Atomic, Molecular, and Optical Physics

Background:

• Trapped ion quantum processors are promising for quantum computation.
• Efficient photon collection and ion excitation are critical for entanglement generation.
• Scalable designs are needed for larger quantum systems.

Purpose of the Study:

• To present a compact optical design for scalable trapped ion quantum processors.
• To enable efficient remote entanglement generation using a single high numerical aperture lens.
• To facilitate the simultaneous generation of multiple entangled qubit pairs.

Main Methods:

• A compact optical design utilizing a single high numerical aperture lens was developed.
• The design was verified through a quantum interference experiment.
• Two photons from separate processor sets were interfered to test indistinguishability.

Main Results:

• A high suppression of coincidence (82(3)%) was observed within an 8.13 ns time window for indistinguishable photons.
• The optical design proved effective for photon generation and collection.
• The design demonstrated potential for scalability.

Conclusions:

• The proposed compact optical design is suitable for scalable trapped ion quantum processors.
• This design facilitates efficient remote entanglement generation.
• The system can be extended for simultaneous multi-qubit entangled pair generation using fiber-array devices.