Continuous variable quantum communication with bright entangled optical beams

Abstract

In this paper, we briefly introduce the basic concepts and protocols of continuous variable quantum communication, and then summarize the experimental researches accomplished by our group in this field. The main features of quantum communication systems used in our experiments are: (1) The bright entangled optical beams with the anticorrelated amplitude quadratures and the correlated phase quadratures that serve as the entanglement resources and (2) The Bell-state direct detection systems are utilized in the measurements of quantum entanglement and transmitted signals instead of the usually balanced homodyne detectors.