title: Optical Phase Conjugation with Less Than a Photon per Degree of Freedom.
abstract: We demonstrate experimentally that optical phase conjugation can be used to focus light through strongly scattering media even when far less than a photon per optical degree of freedom is detected. We found that the best achievable intensity contrast is equal to the total number of detected photons, as long as the resolution of the system is high enough. Our results demonstrate that phase conjugation can be used even when the photon budget is extremely low, such as in high-speed focusing through dynamic media or imaging deep inside tissue.
authors.affiliation: Electrical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, USA.
authors.forename: M
authors.initials: M
authors.lastname: Jang
authors.affiliation: Electrical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, USA.
authors.forename: C
authors.initials: C
authors.lastname: Yang
authors.affiliation: Biomedical Photonic Imaging Group, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, P.O. Box 217, 7500 AE Enschede, Netherlands.
authors.forename: I M
authors.initials: IM
authors.lastname: Vellekoop