dorsal/arxiv
View SchemaOptimal Eavesdropping in Quantum Cryptography. I
| Authors | Christopher A. Fuchs, Nicolas Gisin, Robert B. Griffiths, Chi-Sheng Niu, Asher Peres |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/9701039 |
| URL | https://arxiv.org/abs/quant-ph/9701039 |
Abstract
We consider the Bennett-Brassard cryptographic scheme, which uses two conjugate quantum bases. An eavesdropper who attempts to obtain information on qubits sent in one of the bases causes a disturbance to qubits sent in the other basis. We derive an upper bound to the accessible information in one basis, for a given error rate in the conjugate basis. Independently fixing the error rate in the conjugate bases, we show that both bounds can be attained simultaneously by an optimal eavesdropping probe, consisting of two qubits. The qubits' interaction and their subsequent measurement are described explicitly. These results are combined to give an expression for the optimal information an eavesdropper can obtain for a given average disturbance when her interaction and measurements are performed signal by signal. Finally, the relation between quantum cryptography and violations of Bell's inequalities is discussed.
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"abstract": "We consider the Bennett-Brassard cryptographic scheme, which uses two\nconjugate quantum bases. An eavesdropper who attempts to obtain information on\nqubits sent in one of the bases causes a disturbance to qubits sent in the\nother basis. We derive an upper bound to the accessible information in one\nbasis, for a given error rate in the conjugate basis. Independently fixing the\nerror rate in the conjugate bases, we show that both bounds can be attained\nsimultaneously by an optimal eavesdropping probe, consisting of two qubits. The\nqubits\u0027 interaction and their subsequent measurement are described explicitly.\nThese results are combined to give an expression for the optimal information an\neavesdropper can obtain for a given average disturbance when her interaction\nand measurements are performed signal by signal. Finally, the relation between\nquantum cryptography and violations of Bell\u0027s inequalities is discussed.",
"arxiv_id": "quant-ph/9701039",
"authors": [
"Christopher A. Fuchs",
"Nicolas Gisin",
"Robert B. Griffiths",
"Chi-Sheng Niu",
"Asher Peres"
],
"categories": [
"quant-ph"
],
"title": "Optimal Eavesdropping in Quantum Cryptography. I",
"url": "https://arxiv.org/abs/quant-ph/9701039"
},
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