Illustration showing how single-photon detection is used for feedback. (image) American Institute of Physics Share Print E-Mail Caption Illustration showing how single-photon detection is used for feedback. Once correct parameters for the reference beam are established, the input state is extinguished. Credit Ivan Burenkov Usage Restrictions Journalists may use this image only with appropriate credit. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.