A novel diffused photon-pair density wave (DPPDW) composed of correlated polarized photon pairs at different temporal frequencies and orthogonal linearly polarized states is proposed. A theory of DPPDWs is developed. A DPPDW selected by coherence gating and polarization gating that satisfies the diffusion equation has been verified experimentally. The sensitivity of amplitude and phase detection of the heterodyne signal has been improved by the properties of synchronized detection and common-path propagation of polarized pair photons in a multiple-scattering medium. Both reduced scattering coefficient µ_2s' and absorption coefficient µ_2a of the scattering medium in terms of the measured phase and amplitude of the heterodyne signal have been obtained. The detection sensitivity of µ_2s' and µ_2a and the properties of a DPPDW in a multiple-scattering medium are discussed and analyzed.
© 2005 Optical Society of America
(120.3180) Instrumentation, measurement, and metrology : Interferometry
(170.5270) Medical optics and biotechnology : Photon density waves
(170.5280) Medical optics and biotechnology : Photon migration
(170.7050) Medical optics and biotechnology : Turbid media
(290.4210) Scattering : Multiple scattering
Yi-Hsin Chan, Chien Chou, Jheng-Syong Wu, Hsiu-Fong Chang, and Hon-Fai Yau, "Properties of a diffused photon-pair density wave in a multiple-scattering medium," Appl. Opt. 44, 1416-1425 (2005)