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Two-Photon Mode Preparation and Matching Efficiency: Definition, Measurement and Optimization



Stefania Castelletto, Ivo P. Degiovanni, G Furno, V Schettini, Alan L. Migdall, M J. Ware


We investigate the coupling efficiency of parametric down conversion (PDC) into single and multi modes optical fibers, as a function of the pump beam mode diameter, crystal length and walk-off. We outline two different theoretical models for the preparation and collection of either single mode or multi-modes of PDC (given for instance by multi-mode fibers or regular apertures). Moreover we define the mode-matching collection efficiency that is crucial for realizing a single photon source based on PDC in a well defined single mode, versus the multi mode collection efficiency that is useful for single photon detector calibration applications.
IEEE Transactions on Instrumentation and Measurement
No 2


metrology, mode coupling, multimode, parametric down conversion, PDC, quantum information, single mode, single photon, single photon source


Castelletto, S. , Degiovanni, I. , Furno, G. , Schettini, V. , Migdall, A. and Ware, M. (2005), Two-Photon Mode Preparation and Matching Efficiency: Definition, Measurement and Optimization, IEEE Transactions on Instrumentation and Measurement, [online], (Accessed June 17, 2024)


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Created March 31, 2005, Updated October 12, 2021