Quantum Key Distribution Scheme Based on Dense Encoding in Entangled States

Abstract

A quantum key distribution protocol, based on the quantum dense encoding inentangled states, is presented. In this protocol, we introduce an encodingprocess to encode two classical bits information into one of the four one-qubitunitary operations implemented by Alice and the Bell states measurementimplemented by Bob in stead of direct measuring the previously sharedEinstein–Podolsky–Rosen pairs by both of the distant parties, Alice and Bob.Considering the practical application we can get the conclusion that ourprotocol has some advantages. It not only simplifies the measurement which mayinduce potential errors, but also improves the effectively transmitted rate ofthe generated qubits by the raw key. Here we also discuss eavesdroppingattacks against the scheme and the channel loss.