dorsal/arxiv
View SchemaSecure communication with single-photon two-qubit states
| Authors | Almut Beige, Berthold-Georg Englert, Christian Kurtsiefer, Harald Weinfurter |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0101066 |
| URL | https://arxiv.org/abs/quant-ph/0101066 |
| DOI | 10.1088/0305-4470/35/28/103 |
| Journal | J. Phys. A 35, L407 (2002) |
Abstract
We propose a cryptographic scheme that is deterministic: Alice sends single photons to Bob, and each and every photon detected supplies one key bit -- no photon is wasted. This is in marked contrast to other schemes in which a random process decides whether the next photon sent will contribute to the key or not. The determinism is achieved by preparing the photons in two-qubit states, rather than the one-qubit states used in conventional schemes. In particular, we consider the realistic situation in which one qubit is the photon polarization, the other a spatial alternative. Further, we show how one can exploit the deterministic nature for direct secure communication, that is: without the need for establishing a shared key first.
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"abstract": "We propose a cryptographic scheme that is deterministic: Alice sends single\nphotons to Bob, and each and every photon detected supplies one key bit -- no\nphoton is wasted. This is in marked contrast to other schemes in which a random\nprocess decides whether the next photon sent will contribute to the key or not.\nThe determinism is achieved by preparing the photons in two-qubit states,\nrather than the one-qubit states used in conventional schemes. In particular,\nwe consider the realistic situation in which one qubit is the photon\npolarization, the other a spatial alternative. Further, we show how one can\nexploit the deterministic nature for direct secure communication, that is:\nwithout the need for establishing a shared key first.",
"arxiv_id": "quant-ph/0101066",
"authors": [
"Almut Beige",
"Berthold-Georg Englert",
"Christian Kurtsiefer",
"Harald Weinfurter"
],
"categories": [
"quant-ph"
],
"doi": "10.1088/0305-4470/35/28/103",
"journal_ref": "J. Phys. A 35, L407 (2002)",
"title": "Secure communication with single-photon two-qubit states",
"url": "https://arxiv.org/abs/quant-ph/0101066"
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