0000000000465017
AUTHOR
Hanna Lajunen
‘Nonlocal’ dispersion cancelation with classical light
We show a classical analog of the original nonlocal dispersion cancelation effect in intensity interferometry with stationary light obeying Gaussian statistics. The dispersion compensation is due to the uncorrelation of the spectral components of the radiation. Although this classical counterpart phenomenon is not nonlocal in a strict quantum mechanical sense, it suggests that some second-order interference devices relying on temporal entanglement do not require a quantum light source.
“Nonlocal” dispersion cancellation with classical light
Nonlocal dispersion cancellation [1] is a quantum phenomenon that relies on the use of a quantum light source, e.g., spontaneous parametric down-conversion (SPDC), providing temporally entangled photon pairs. Each photon in the pair propagates through a dispersive medium [see Fig. 1 (a)]. Under suitable conditions the dispersion of one photon cancels out the dispersion of the other photon, so that their intensity coincidence probability remains unchanged. Nonlocal dispersion cancellation has been experimentally demonstrated [2] and this phenomenon has subsequently triggered important applications in quantum information science, such as quantum-optical coherence tomography, distant clock syn…
Communication modes in vector diffraction
The communication modes, which mathematically correspond to singular value decomposition, have proven a useful concept in optical scalar-field diffraction, with applications in resolution studies, image synthesis, and wave propagation. For optical near-field geometries the communication modes have to be extended to electromagnetic field accounting for the polarization properties. In this paper we present the vector-valued communication modes method based on the rigorous electric-field diffraction integral. As a special case the transverse-electric scalar field modes are obtained. The intensity and polarization properties of the leading electromagnetic communication modes in near-field arran…
Resolution-enhanced optical coherence tomography based on classical intensity interferometry.
We propose a fourth-order interference scheme for optical coherence tomography operating with broadband incoherent (or quasi-incoherent) light. It is shown that using this proposal, an axial resolution improvement by a factor of 2 and a better sensitivity for weakly reflecting samples are obtained than with the standard second-order correlation scheme. From a practical perspective, we suggest the use of broadband Q-switched pulses and performing ultrafast intensity correlation with a nonlinear crystal. The global performance of our proposal is illustrated by means of numerical simulations
Pulse-by-pulse method to characterize partially coherent pulse propagation in instantaneous nonlinear media.
We propose a numerical method for analyzing extensively the evolution of the coherence functions of nonstationary optical pulses in dispersive, instantaneous nonlinear Kerr media. Our approach deals with the individual propagation of samples from a properly selected ensemble that reproduces the coherence properties of the input pulsed light. In contrast to the usual strategy assuming Gaussian statistics, our numerical algorithm allows us to model the propagation of arbitrary partially coherent pulses in media with strong and instantaneous nonlinearities.