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Tests of a Two-Photon Technique for Measuring Polarization Mode Dispersion With Subfemtosecond Precision



Eric Dauler, Gregg Jaeger, A Muller, Alan L. Migdall


An investigation is made of a recently introduced quantum interferometric method capable of measuring polarization mode dispersion (PMD) on sub-femtosecond scales, without the usual interferometric stability problems associated with such small time scales. The technique makes use of the extreme temporal correlation of orthogonally polarized pairs of photons produced via type-II phase-matched spontaneous parametric down-conversion. When sent into a simple polarization interferometer these photon pairs produce a sharp interference feature seen in the coincidence rate. The PMD of a given sample is determined from the shift of that interference feature as the sample is inserted into the system. The stability and resolution of this technique is shown to be below 0.2 fs. We explore how this precision is improved by reducing the length of the down-conversion crystal and increasing the spectral band pass of the system.
Journal of Research (NIST JRES) -


group velocity delay, optical delay, parametric downconversion, polarization interferometer, polarization mode dispersion, quantum interference


Dauler, E. , Jaeger, G. , Muller, A. and Migdall, A. (1999), Tests of a Two-Photon Technique for Measuring Polarization Mode Dispersion With Subfemtosecond Precision, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed June 22, 2024)


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Created December 31, 1998, Updated October 12, 2021