Patent ID: 9294191
Filing Date: 2016-03-22
CPC Classification: H04B,H04L

Claim Text:
1. A system for quantum communications, comprising: a source of photons, the source configured to place a signal photon and an idler photon in individual unknown quantum states and in a known entangled quantum state; one or more pair of transmission channels connected to the source, each of the pair of transmission channels configured to transport one of the signal photon or the idler photon, each of the pair of transmission channels configured to substantially balance an instantaneous transmission loss with an instantaneous transmission gain distributed over a transmission distance; one or more analysis interferometers, each configured to receive a corresponding one of the signal photon or the idler photon, configured to perform a basis measurement on one of the signal photon or the idler photon; and one or more single-photon detectors at an output of the analysis interferometers for detecting one of the signal photon or the idler photon.