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Tailoring photonic entanglement in high-dimensional Hilbert spaces

Hugues de Riedmatten·Ivan Marcikic·Valerio Scarani·Wolfgang Tittel·Hugo Zbinden·Nicolas Gisin
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Abstract

We present an experiment where two photonic systems of arbitrary dimensions can be entangled. The method is based on spontaneous parametric down conversion with trains of d pump pulses with a fixed phase relation, generated by a mode-locked laser. This leads to a photon pair created in a coherent superposition of $d$ discrete emission times, given by the successive laser pulses. Entanglement is shown by performing a two-photon interference experiment and by observing the visibility of the interference fringes increasing as a function of the dimension d. Factors limiting the visibility, such as the presence of multiple pairs in one train, are discussed.

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Hugues de Riedmatten, Ivan Marcikic, Valerio Scarani, Wolfgang Tittel, Hugo Zbinden, Nicolas Gisin. 2004-09-15. Tailoring photonic entanglement in high-dimensional Hilbert spaces. https://doi.org/10.1103/physreva.69.050304

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