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A Dual Scale Two-Photon Technique for Measuring Polarization Mode Dispersion With Attosecond Resolution



Alan L. Migdall, A Muller, G Jaeger, A V. Sergienko


We describe a highly stable dual scale technique for measuring polarization mode dispersion (PMD) using entangled two-photon states produced via Type-II spontaneous parametric down conversion. The method relies on locating the center of a two-photon interference feature, the position of which depends on the relative propagation times of orthogonally polarized photons. That interference pattern consists of an envelope filled with fine fringes resulting in two characteristic time scales. The coarser of the two scales, the one associated with the width of the envelope, which can be made as short as 8 fs, has already been demonstrated to allow for resolutions of better than 0.2 fs. The second scale, with a {approximately} 1 fs width, offers significant potential improvement in resolution over the original scale. This new, finer scale arises from a modification of a previously reported two-photon polarization interferometer. This modification uses what has been referred to as postponed compensation. One advantage of such a two scale measurement is that it allows high time resolutions with relatively narrow band light. That is, the improved measurement resolution is not obtained simply by broadening optical bandwidth to reduce the coherence time.
Physical Review Letters


correlation, entangled states, optical delay, parametric down conversion, PMD, polarization mode dispersion, quantum interference, two-photons


Migdall, A. , Muller, A. , Jaeger, G. and Sergienko, A. (2010), A Dual Scale Two-Photon Technique for Measuring Polarization Mode Dispersion With Attosecond Resolution, Physical Review Letters (Accessed May 19, 2024)


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Created November 10, 2010, Updated February 17, 2017