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Updated: May 9, 2026
09:23
Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
Complete tomography of a high-fidelity solid-state entangled spin-photon qubit pair
Kristiaan De Greve1, Peter L McMahon, Leo Yu
1E. L. Ginzton Laboratory, Stanford University, Stanford, California 94305, USA. kdegreve@stanford.edu
Nature Communications
|July 27, 2013
Summary
Researchers achieved high-fidelity spin-photon entanglement in solid-state systems, a key step for quantum networks. This breakthrough overcomes previous limitations, enabling robust quantum communication over longer distances.
Area of Science:
- Quantum Information Science
- Solid-State Physics
- Quantum Communication
Background:
- Entanglement between quantum memories and photonic qubits is vital for quantum networks.
- Solid-state systems offer scalability but face fidelity challenges due to environmental interactions.
Purpose of the Study:
- To demonstrate high-fidelity spin-photon entanglement in a solid-state system.
- To enable practical quantum repeater networks by overcoming fidelity limitations.
Main Methods:
- Complete state tomography of a spin-photon-polarization-entangled qubit pair.
- Utilized a single electron-charged indium arsenide quantum dot.
Main Results:
- Achieved record-high entanglement fidelity (>90%) in a solid-state system.
- Demonstrated fidelity (99.9%-confidence) sufficient for quantum repeater networks.
Conclusions:
- This work establishes a new benchmark for solid-state spin-photon entanglement.
- The achieved fidelity paves the way for scalable solid-state quantum repeater networks.
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