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arXiv · 2108.08290

Non-Gaussian photonic state engineering with the quantum frequency processor

Andrew J. Pizzimenti·Joseph M. Lukens·Hsuan-Hao Lu·Nicholas A. Peters·Saikat Guha·Christos N. Gagatsos
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Abstract

Non-Gaussian quantum states of light are critical resources for optical quantum information processing, but methods to generate them efficiently remain challenging to implement. Here we introduce a generic approach for non-Gaussian state production from input states populating discrete frequency bins. Based on controllable unitary operations with a quantum frequency processor, followed by photon-number-resolved detection of ancilla modes, our method combines recent developments in both frequency-based quantum information and non-Gaussian state preparation. Leveraging and refining the K-function representation of quantum states in the coherent basis, we develop a theoretical model amenable to numerical optimization and, as specific examples, design quantum frequency processor circuits for the production of Schr\"{o}dinger cat states, exploring the performance tradeoffs for several combinations of ancilla modes and circuit depth. Our scheme provides a valuable general framework for producing complex quantum states in frequency bins, paving the way for single-spatial-mode, fiber-optic-compatible non-Gaussian resource states.

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Andrew J. Pizzimenti, Joseph M. Lukens, Hsuan-Hao Lu, Nicholas A. Peters, Saikat Guha, Christos N. Gagatsos. 2021-08-18. Non-Gaussian photonic state engineering with the quantum frequency processor. https://doi.org/10.1103/physreva.104.062437

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