Experimentally realizable quantum comparison of coherent states and its applications

Erika Andersson, Marcos Curty, Igor Jex

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99 Citations (Scopus)


When comparing quantum states to each other, it is possible to obtain an unambiguous answer, indicating that the states are definitely different, already after a single measurement. In this paper we investigate comparison of coherent states, which is the simplest example of quantum state comparison for continuous variables. The method we present has a high success probability, and is experimentally feasible to realize as the only required components are beam splitters and photon detectors. An easily realizable method for quantum state comparison could be important for real applications. As examples of such applications we present a "lock and key" scheme and a simple scheme for quantum public key distribution.

Original languageEnglish
Article number022304
Pages (from-to)-
Number of pages11
JournalPhysical Review A
Issue number2
Publication statusPublished - 3 Aug 2006

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