Title :
Conference key agreement and quantum sharing of classical secrets with noisy GHZ states
Author :
Chen, Kai ; Lo, Hoi-Kwong
Author_Institution :
Dept. of Electr. & Comput. Eng., Toronto Univ., Ont.
Abstract :
We propose a wide class of distillation schemes for multi-partite entangled states that are CSS-states. Our proposal provides not only superior efficiency, but also new insights on the connection between CSS-states and bipartite graph states. We then consider the applications of our distillation schemes for two cryptographic tasks - namely, (a) conference key agreement and (b) quantum sharing of classical secrets. In particular, we construct "prepare-and-measure" protocols. Also we study the yield of those protocols and the threshold value of the fidelity above which the protocols can function securely. Surprisingly, our protocols function securely even when the initial state does not violate the standard Bell-inequalities for GHZ states. Experimental realization involving only bipartite entanglement is also suggested
Keywords :
cryptography; graph theory; protocols; quantum theory; bipartite graph states; conference key agreement; cryptographic tasks; distillation schemes; prepare-and-measure protocols; quantum sharing; standard Bell-inequalities; Bipartite graph; Cascading style sheets; Cryptographic protocols; Cryptography; Paramagnetic resonance; Physics; Proposals; Quantum computing; Quantum entanglement; Quantum mechanics;
Conference_Titel :
Information Theory, 2005. ISIT 2005. Proceedings. International Symposium on
Conference_Location :
Adelaide, SA
Print_ISBN :
0-7803-9151-9
DOI :
10.1109/ISIT.2005.1523616