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Published on: August 2, 2019
Qubit teleportation and transfer across antiferromagnetic spin chains
L Campos Venuti1, C Degli Esposti Boschi, M Roncaglia
1Institute for Scientific Interchange, Villa Gualino, viale Settimio Severo 65, I-10133 Torino, Italy.
Physical Review Letters
|October 13, 2007
Summary
Spin-1/2 chains can serve as quantum channels for teleportation and qubit transfer. High communication fidelities are achievable even with temperature effects, using specific antiferromagnetic systems.
Area of Science:
- Quantum information science
- Condensed matter physics
- Quantum communication
Background:
- Long-distance entanglement in low-dimensional spin systems is a key resource.
- Quantum channels are essential for transmitting quantum information.
- Previous studies have not fully accounted for thermal effects in such channels.
Purpose of the Study:
- To investigate the potential of spin-1/2 chains as quantum channels.
- To analyze protocols for quantum teleportation and qubit transfer.
- To assess the impact of temperature on channel fidelity.
Main Methods:
- Utilizing the phenomenon of emergent long-distance entanglement.
- Modeling teleportation and state transfer protocols.
- Analyzing antiferromagnetic rotationally invariant spin systems.
- Representing protocols as pure depolarizing channels.
Main Results:
- Demonstrated high communication fidelities between distant parties.
- Showcased the effectiveness of spin chains as quantum channels.
- Investigated the influence of temperature on protocol performance.
- Achieved channel fidelity close to 1 for long chains at moderate temperatures.
Conclusions:
- Spin-1/2 chains are viable quantum channels for teleportation and qubit transfer.
- High fidelities are attainable even under realistic thermal conditions.
- The proposed scheme offers a promising route for robust quantum communication over long distances.
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