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arXiv · 2606.31150

Energetics of non-Gaussianity in single mode cavities

Sahil Sardar Jafar·Kian Hwee Lim·Kiarn T. Laverick·Samyak P. Prasad·Maria Maffei·Alexia Auffèves
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Abstract

Non-Gaussian states play a central role in quantum technologies, making the ability to quantify non-Gaussianity essential. We introduce an energetic framework to characterize non-Gaussianity in single-mode bosonic states by decomposing the total energy into Gaussian and non-Gaussian contributions. For pure states, we show that the non-Gaussian component defines a valid measure of non-Gaussianity and establish its connection to the relative entropy of non-Gaussianity. As an illustration, we compare this measure with Wigner negativity and find that both are maximized in closely related parameter regimes. For mixed states, we demonstrate that the non-Gaussian contribution acts as a faithful witness of non-Gaussianity. Our results reveal an energetic fine structure underlying non-Gaussianity and may provide practical insights for the efficient generation of non-Gaussian states.

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Sahil Sardar Jafar, Kian Hwee Lim, Kiarn T. Laverick, Samyak P. Prasad, Maria Maffei, Alexia Auffèves. 2026-06-30. Energetics of non-Gaussianity in single mode cavities. https://arxiv.org/abs/2606.31150

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