dorsal/arxiv
View SchemaOptimal state encoding for quantum walks and quantum communication over spin systems
| Authors | Henry L. Haselgrove |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0404152 |
| URL | https://arxiv.org/abs/quant-ph/0404152 |
| DOI | 10.1103/PhysRevA.72.062326 |
| Journal | Phys. Rev. A 72, 062326 (2005) |
Abstract
Recent work has shown that a simple chain of interacting spins can be used as a medium for high-fidelity quantum communication. We describe a scheme for quantum communication using a spin system that conserves z-spin, but otherwise is arbitrary. The sender and receiver are assumed to directly control several spins each, with the sender encoding the message state onto the larger state-space of her control spins. We show how to find the encoding that maximises the fidelity of communication, using a simple method based on the singular-value decomposition. Also, we show that this solution can be used to increase communication fidelity in a rather different circumstance: where no encoding of initial states is used, but where the sender and receiver control exactly two spins each and vary the interactions on those spins over time. The methods presented are computationally efficient, and numerical examples are given for systems having up to 300 spins.
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"abstract": "Recent work has shown that a simple chain of interacting spins can be used as\na medium for high-fidelity quantum communication. We describe a scheme for\nquantum communication using a spin system that conserves z-spin, but otherwise\nis arbitrary. The sender and receiver are assumed to directly control several\nspins each, with the sender encoding the message state onto the larger\nstate-space of her control spins. We show how to find the encoding that\nmaximises the fidelity of communication, using a simple method based on the\nsingular-value decomposition. Also, we show that this solution can be used to\nincrease communication fidelity in a rather different circumstance: where no\nencoding of initial states is used, but where the sender and receiver control\nexactly two spins each and vary the interactions on those spins over time. The\nmethods presented are computationally efficient, and numerical examples are\ngiven for systems having up to 300 spins.",
"arxiv_id": "quant-ph/0404152",
"authors": [
"Henry L. Haselgrove"
],
"categories": [
"quant-ph"
],
"doi": "10.1103/PhysRevA.72.062326",
"journal_ref": "Phys. Rev. A 72, 062326 (2005)",
"title": "Optimal state encoding for quantum walks and quantum communication over spin systems",
"url": "https://arxiv.org/abs/quant-ph/0404152"
},
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