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arXiv · 2412.07417

Cross-spectral purity: a generalization of spatiotemporal separability

Matias Koivurova·Rajneesh Joshi
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Abstract

We study the connection between cross-spectral purity and spatiotemporal separability of nonstationary (pulsed) scalar fields. It is found that in the case of complete coherence, there is a two-way relation between global cross-spectral purity and spatiotemporal separability of the field. Moreover, we show that cross-spectral purity generalizes the notion of spatiotemporal separability to partially coherent fields, due to the separability of the correlation functions. We also briefly discuss simple self-referencing linear measurement methods that can reveal cross-spectral purity.

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Matias Koivurova, Rajneesh Joshi. 2024-12-10. Cross-spectral purity: a generalization of spatiotemporal separability. https://arxiv.org/abs/2412.07417

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