Noise-enhanced classical and quantum capacities in communication networks

Phys Rev Lett. 2010 Nov 5;105(19):190501. doi: 10.1103/PhysRevLett.105.190501. Epub 2010 Nov 2.

Abstract

The unavoidable presence of noise is thought to be one of the major problems to solve in order to pave the way for implementing quantum information technologies in realistic physical platforms. However, here we show a clear example in which noise, in terms of dephasing, may enhance the capability of transmitting not only classical but also quantum information, encoded in quantum systems, through communication networks. In particular, we find analytically and numerically the quantum and classical capacities for a large family of quantum channels and show that these information transmission rates can be strongly enhanced by introducing dephasing noise in the complex network dynamics.