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Universal control and error correction in multi-qubit spin registers in diamond.
T H Taminiau1, J Cramer1, T van der Sar2
1Kavli Institute of Nanoscience, Delft University of Technology, PO Box 5046, 2600 GA Delft, The Netherlands.
Nature Nanotechnology
|February 4, 2014
Summary
Researchers harnessed weakly coupled nuclear spins for quantum computing. This breakthrough enables high-fidelity control over multi-qubit spin registers, advancing quantum information processing and error correction.
Area of Science:
- Quantum Information Science
- Solid-State Physics
- Quantum Computing
Background:
- Quantum registers utilizing electron spins of solid-state defects are promising for quantum information processing.
- Previous research focused on defects with strongly coupled nuclear spins.
- Scaling up quantum registers requires larger, deterministically available nuclear spin systems.
Purpose of the Study:
- To develop universal control over multi-qubit spin registers using abundant, weakly coupled nuclear spins.
- To demonstrate the feasibility of using these registers for quantum error correction.
Main Methods:
- Utilized the electron spin of a nitrogen-vacancy center in diamond.
- Achieved selective initialization, control, and readout of surrounding carbon-13 nuclear spins.
- Constructed high-fidelity single- and two-qubit gates.
Main Results:
- Demonstrated universal control over multi-qubit spin registers composed of weakly coupled nuclear spins.
- Implemented a three-qubit quantum error correction protocol.
- Showcased the encoded state's robustness against applied errors.
Conclusions:
- Weakly coupled nuclear spins can be transformed from a source of decoherence into a reliable quantum resource.
- This approach paves the way for extended quantum networks and surface-code quantum computing.
- Enables the development of multi-qubit nodes for scalable quantum technologies.
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