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Counter-propagating entangled photons from a waveguide with periodic nonlinearity

Mark C. Booth·Mete Atature·Giovanni Di Giuseppe·Alexander V. Sergienko·Bahaa E. A. Saleh·Malvin C. Teich
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Abstract

The conditions required for spontaneous parametric down-conversion in a waveguide with periodic nonlinearity in the presence of an unguided pump field are established. Control of the periodic nonlinearity and the physical properties of the waveguide permits the quasi-phase matching equations that describe counter-propagating guided signal and idler beams to be satisfied. We compare the tuning curves and spectral properties of such counter-propagating beams to those for co-propagating beams under typical experimental conditions. We find that the counter-propagating beams exhibit narrow bandwidth permitting the generation of quantum states that possess discrete-frequency entanglement. Such states may be useful for experiments in quantum optics and technologies that benefit from frequency entanglement.

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Mark C. Booth, Mete Atature, Giovanni Di Giuseppe, Alexander V. Sergienko, Bahaa E. A. Saleh, Malvin C. Teich. 2002-01-31. Counter-propagating entangled photons from a waveguide with periodic nonlinearity. https://doi.org/10.1103/physreva.66.023815

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