Quantum key distribution system clocked at 2 GHz.

Optics Express (Impact Factor: 3.53). 05/2005; 13(8):3015-20. DOI: 10.1364/OPEX.13.003015
Source: PubMed

ABSTRACT An improved quantum key distribution test system operating at clock rates of up to 2GHz using a specially adapted commercially-available silicon single-photon counting module is presented. The use of an enhanced detector has improved the fiber-based quantum key distribution test system performance in terms of transmission distance and quantum bit error rate.

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    ABSTRACT: Present paper provides a conceptual framework on the proposed C-QUBITS Key exchange technique, which is used as a base for the data security through quantum computing in the modern cryptosystem. In the first phase a detailed description of the BB84 Cryptographic protocol is given, which is used as a standard protocol for quantum key distribution in quantum cryptography and the emphasis is also given on the loopholes present in this protocol which makes it less effective than it pretends to be. In the next phase the focus is made on the C-QUBITS technique, which can be used for the exchange of key between the sender and the receiver. Thereafter the key is used for the encryption of the data to be transferred between the two entities. This technique makes use of the concepts of quantum physics like polarization and more importantly C-NOT gate which is mainly used in case of qubits (quantum bits) and it is more effective and secure than the BB84 protocol. In the last phase the focus is made on the information reconciliation and privacy amplification, which is used for error correction carried out between Alice and Bob's keys and for reducing a third party's partial information about the shared secret key between two parties, Alice and Bob respectively. Further the security level in the C-QUBITS technique can be increase by performing the privacy amplification that convert the realized secret key into a smaller length key through some hashing function chosen at random from a known set of hashing functions.
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