Secure communication with single-photon two-qubit states
摘要
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.
引用
@article{arxiv.quant-ph/0101066,
title = {Secure communication with single-photon two-qubit states},
author = {Almut Beige and Berthold-Georg Englert and Christian Kurtsiefer and Harald Weinfurter},
journal= {arXiv preprint arXiv:quant-ph/0101066},
year = {2009}
}
备注
9 pages, 1 figure, 3 tables; final version