title: Origin of low-coherence enhanced backscattering.
abstract: The origin of low-coherence enhanced backscattering (EBS) of light in random media when the spatial coherence length of illumination is much smaller than the transport mean free path has been poorly understood. We report that in weakly scattering discrete random media low-coherence EBS originates from time-reversed paths of double scattering. Low spatial coherence illumination dephases the time-reversed waves outside its finite coherence area, which isolates the minimal number of scattering events in EBS from higher-order scattering. Moreover, we show the first experimental evidence that the minimal number of scattering events in EBS is double scattering, which has been hypothesized since the first observation of EBS.
authors.affiliation: Biomedical Engineering Department, Northwestern University, Evanston, Illinois 60208, USA. younglae@northwestern.edu
authors.forename: Young L
authors.initials: YL
authors.lastname: Kim
authors.forename: Prabhakar
authors.initials: P
authors.lastname: Pradhan
authors.forename: Hariharan
authors.initials: H
authors.lastname: Subramanian
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.forename: Min H
authors.initials: MH
authors.lastname: Kim
authors.forename: Vadim
authors.initials: V
authors.lastname: Backman
mesh_terms: D000465:Algorithms; D016477:Artifacts; D003198:Computer Simulation; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008954:Models, Biological; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D041623:Tomography, Optical Coherence / Q000379:methods*