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arXiv · 1804.08531

Two-photon self-Kerr nonlinearities for quantum computing and quantum optics

Joshua Combes·Daniel J. Brod
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Abstract

The self-Kerr interaction is an optical nonlinearity that produces a phase shift proportional to the square of the number of photons in the field. At present, many proposals use nonlinearities to generate photon-photon interactions. For propagating fields these interactions result in undesirable features such as spectral correlation between the photons. Here, we engineer a discrete network composed of cross-Kerr interaction regions to simulate a self-Kerr medium. The medium has effective long-range interactions implemented in a physically local way. We compute the one- and two-photon S matrices for fields propagating in this medium. From these scattering matrices we show that our proposal leads to a high fidelity photon-photon gate. In the limit where the number of nodes in the network tends to infinity, the medium approximates a perfect self-Kerr interaction in the one- and two-photon regime.

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Joshua Combes, Daniel J. Brod. 2018-04-23. Two-photon self-Kerr nonlinearities for quantum computing and quantum optics. https://doi.org/10.1103/physreva.98.062313

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