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Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots
Published on: November 1, 2013
Practicality of spin chain wiring in diamond quantum technologies
Yuting Ping1, Brendon W Lovett, Simon C Benjamin
1Department of Materials, University of Oxford, Oxford OX1 3PH, United Kingdom.
Physical Review Letters
|March 26, 2013
Summary
Coupled spin chains in diamond show potential for quantum computing (QC) but face fidelity challenges. Repurposing them for noisy entanglement mediation with purification offers a viable path for QC, even without nearest-neighbor interactions.
Area of Science:
- Quantum Information Science
- Solid-State Quantum Computing
- Nitrogen-Vacancy Centers in Diamond
Background:
- Coupled spin chains, particularly those using nitrogen-vacancy centers in diamond, are explored for quantum computing applications.
- These systems aim to enable quantum state transfer at room temperature via implanted nitrogen impurities.
Purpose of the Study:
- To analyze the error effects on coupled spin chains for quantum computing.
- To investigate the potential of these chains as mediators of noisy entanglement for quantum computing, even with fidelity limitations.
Main Methods:
- Detailed analysis of error effects in coupled spin chain systems.
- Investigation of entanglement capabilities of a 5-spin chain with 10 nm interspin distances.
- Assessment of T(2) time requirements for finite entangling power.
Main Results:
- Foreseeable coupled spin chain systems may not achieve the high fidelities required for quantum computing.
- A chain of 5 spins requires a T(2) time exceeding 0.55 ms for finite entangling power.
- Repurposing chains for entanglement mediation removes the need for nearest-neighbor interactions and complex dynamical decoupling sequences.
Conclusions:
- Coupled spin chains can function as mediators of noisy entanglement, enabling quantum computing when combined with subsequent purification.
- This approach relaxes stringent requirements on spin interactions, simplifying system design.
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