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On the scalability of parametric down-conversion for generating higher-order Fock states



Thomas Gerrits, Adriana Lita, Sae Woo Nam, Johannes Tiedau, Tim J. Bartley, Georg Harder, Christine Silberhorn


Spontaneous parametric down-conversion (SPDC) is the most widely-used method to generate higher-order Fock states (n>2). Yet, a consistent performance analysis from fundamental principles is missing. Here we address this problem by analyzing state fidelity and generation probability under the consideration of losses and multimode emission. With this analysis we show the fundamental limitations of this process as well as a trade-o between state fidelity and generation rate intrinsic to the probabilistic nature of the process. This identifies the parameter space for which SPDC is useful when generating higher-order Fock states for quantum applications. We experimentally investigate the strong pump regime of SPDC and demonstrate heralded Fock states up to |n> = 4.
Physical Review


squeezing, photon number resolution, quantum informtation


Gerrits, T. , Lita, A. , Nam, S. , Tiedau, J. , Bartley, T. , Harder, G. and Silberhorn, C. (2018), On the scalability of parametric down-conversion for generating higher-order Fock states, Physical Review, [online], (Accessed May 19, 2024)


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Created October 18, 2018, Updated April 9, 2024