Identification and Control of Electron-Nuclear Spin Defects in Diamond

Area of Science:

• Quantum physics
• Quantum information science
• Solid-state quantum systems

Background:

• Scaling quantum devices is crucial for advancing quantum sensing and information processing.
• Nitrogen-vacancy (NV) centers in diamond are promising solid-state qubits.
• Controlling multiple spin defects is essential for building complex quantum registers.

Purpose of the Study:

• To demonstrate an experimental approach for scaling quantum devices using environmental spin defects.
• To identify, locate, and control two electron-nuclear spin defects near a single NV center.
• To establish quantum coherence among multiple electron spins for entanglement generation.

Main Methods:

• Utilizing a single nitrogen-vacancy center as a quantum probe.
• Performing multi-axis magnetic field spectroscopy to characterize spin defects.
• Extracting hyperfine and dipolar interaction tensor parameters.
• Designing and implementing quantum control sequences for initialization, manipulation, and readout.
• Creating quantum coherence between electron spins.

Main Results:

• Successfully identified and located two electron-nuclear spin defects.
• Determined unknown hyperfine and dipolar interaction tensor parameters.
• Developed control sequences to precisely manipulate the quantum states of the defects.
• Achieved quantum coherence among three electron spins (one NV center electron spin and two defect electron spins).

Conclusions:

• The demonstrated approach effectively scales quantum devices by harnessing environmental spin defects.
• This work paves the way for creating genuine tripartite entanglement.
• The methodology is applicable to assembling multispin quantum registers for quantum sensing and quantum information processing.