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arXiv · 2007.12429

Hot-spots and gain enhancement in a doubly pumped parametric down-conversion process

Ottavia Jedrkiewicz·Erica Invernizzi·Enrico Brambilla·Alessandra Gatti
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Abstract

We experimentally investigate the parametric down-conversion process in a nonlinear bulk crystal, driven by two non-collinear pump modes. The experiment shows the emergence of bright hot-spots in modes shared by the two pumps, in analogy with the phenomenology recently observed in 2D nonlinear photonic crystals. By exploiting the spatial walk-off between the two extraordinary pump modes we have been able to recreate a peculiar resonance condition, reported by a local enhancement of the parametric gain, which corresponds to a transition from a three-mode to a four-mode coupling. From a quantum point of view this opens the way to the generation of multimode entangled states of light such as tripartite or quadripartite states, in simple bulk nonlinear sources.

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Ottavia Jedrkiewicz, Erica Invernizzi, Enrico Brambilla, Alessandra Gatti. 2020-07-24. Hot-spots and gain enhancement in a doubly pumped parametric down-conversion process. https://doi.org/10.1364/oe.403668

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