Parallel single-shot measurement and coherent control of solid-state spins below the diffraction limit

Area of Science:

• Quantum Science and Technology
• Solid-State Quantum Systems
• Quantum Information Processing

Background:

• Solid-state spin defects are crucial for advancing quantum science and technology.
• Scalable quantum systems require high-fidelity control of multiple defects at nanoscale separations for multi-qubit operations and entanglement.
• Strong spin-spin interactions are essential for quantum logic operations.

Purpose of the Study:

• To demonstrate a method for high-fidelity control and measurement of multiple solid-state spin defects.
• To enable strong spin-spin interactions for quantum information processing applications.
• To advance the development of scalable quantum systems using rare-earth ions.

Main Methods:

• Demonstrated an optical frequency-domain multiplexing technique for controlling rare-earth (Er3+) ions.
• Utilized a single, silicon photonic crystal cavity with subwavelength volume.
• Employed an optical AC Stark shift for subwavelength control over coherent spin rotations.

Main Results:

• Achieved high-fidelity initialization and single-shot spin measurement of six Er3+ ions.
• Demonstrated subwavelength control over coherent spin rotations.
• Showcased the scalability of the approach to large numbers of ions with small separations.

Conclusions:

• The developed optical multiplexing technique is a significant step toward realizing strongly interacting atomic defect ensembles.
• This approach facilitates quantum information processing and fundamental studies of many-body dynamics.
• The method offers a scalable pathway for creating larger-scale quantum systems with solid-state defects.