Deterministic and efficient quantum cryptography based on Bell's theorem

作者:Chen ZB*; Zhang Q; Bao XH; Schmiedmayer J; Pan JW
来源:Physical Review A, 2006, 73(5): 050302.
DOI:10.1103/PhysRevA.73.050302

摘要

We propose a double-entanglement-based quantum cryptography protocol that is both efficient and deterministic. The proposal uses photon pairs with entanglement both in polarization and in time degrees of freedom; each measurement in which both of the two communicating parties register a photon can establish one and only one perfect correlation, and thus deterministically create a key bit. Eavesdropping can be detected by violation of local realism. A variation of the protocol shows a higher security, similar to the six-state protocol, under individual attacks. Our scheme allows a robust implementation under the current technology.