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Using Correlated Photons to Measure Polarization Mode Dispersion with Attosecond Resolution



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


We describe the status of a highly stable dual scale technique for measuring polarization mode dispersion (PMD) using two-photons produced via parametric down conversion. The method uses a two-photon interference to observe relative propagation times of orthogonally polarized photons. The interference pattern consists of an envelope filled with fine fringes, resulting in two characteristic time scales. The coarse scale associated with the width of the envelope can be made as short as 8 fs, while the fine scale due to the fringes has a ~1 fs halfwidth. This new, finer scale arises from a modification of a previous two-photon polarization interferometer, using what has been referred to as postponed compensation. The coarse scale has already demonstrated resolutions as low as 0.15 fs, while the new fine scale offer significant improvement over that result. An advantage of such a two scale measurement is that it allows high time resolutions with relatively narrow band light. That is, the improved temporal measurement resolution is not obtained simply by broadening optical bandwidth to reduce the coherence time. The high stability and precision of this measurement system may allow its use for other applications such as gyroscopes or explorations of the time-energy uncertainty relation.
International Conference on Laser Spectroscopy


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


Migdall, A. , Jaeger, G. and Sergienko, A. (1999), Using Correlated Photons to Measure Polarization Mode Dispersion with Attosecond Resolution, International Conference on Laser Spectroscopy (Accessed April 19, 2024)
Created December 1, 1999, Updated February 17, 2017