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Noise-Resilient Quantum Computing with a Nitrogen-Vacancy Center and Nuclear Spins
J Casanova1, Z-Y Wang1, M B Plenio1
1Institut für Theoretische Physik and IQST, Albert-Einstein-Allee 11, Universität Ulm, D-89069 Ulm, Germany.
Physical Review Letters
|October 8, 2016
Summary
Researchers developed a new protocol for precise quantum control of nuclear spins in diamond using nitrogen-vacancy centers. This method achieves high-fidelity quantum gates, crucial for scalable quantum memory development.
Area of Science:
- Quantum Information Science
- Solid-State Quantum Systems
- Quantum Control
Background:
- Selective control of qubits is essential for quantum information processing.
- Dense spin ensembles in solid-state systems present significant challenges for qubit control.
- Nitrogen-vacancy (NV) centers in diamond are promising platforms for quantum applications.
Purpose of the Study:
- To present a protocol for selective control of electron-nuclear spin ensembles in diamond.
- To achieve a complete set of selective electron-nuclear gates and single nuclear rotations.
- To enable scalable quantum information processing using robust nuclear spin memories.
Main Methods:
- Utilizing a nearby nitrogen-vacancy (NV) center for qubit control.
- Implementing a protocol to suppress internuclear interactions.
- Minimizing unwanted coupling between the NV center and other ensemble spins.
Main Results:
- Achieved high quantum gate fidelities exceeding 99%.
- Demonstrated selective control over electron-nuclear gates and single nuclear rotations.
- Protocol is applicable to weakly coupled, distant spins.
Conclusions:
- The developed protocol offers a scalable method for quantum control in diamond spin ensembles.
- This approach leverages the properties of nuclear spins in diamond as robust quantum memories.
- The high fidelities achieved pave the way for advanced quantum information processing.
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