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arXiv · 2306.00781

Non-perturbative theory of spontaneous parametric down-conversion in open and dispersive optical systems

Aleksa Krstić·Frank Setzpfandt·Sina Saravi
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Abstract

We develop a non-perturbative formulation based on the Green-function quantization method, that can describe spontaneous parametric down-conversion in the high-gain regime in nonlinear optical structures with arbitrary amount of loss and dispersion. This formalism opens the way for description and design of arbitrary complex and/or open nanostructured nonlinear optical systems in quantum technology applications, such as squeezed-light generation, nonlinearity-based quantum sensing, and hybrid quantum systems mediated by nonlinear interactions. As an example case, we numerically investigate the scenario of integrated quantum spectroscopy with undetected photons, in the high-gain regime, and uncover novel gain-dependent effects in the performance of the system.

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Aleksa Krstić, Frank Setzpfandt, Sina Saravi. 2023-06-01. Non-perturbative theory of spontaneous parametric down-conversion in open and dispersive optical systems. https://doi.org/10.1103/physrevresearch.5.043228

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