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arXiv · 2606.05603

Quantum Radar Cross Section with two-photon entangled states

Sunghwa Kang·Jihwan Kim·Zaeill Kim·Duk Y. Kim·Yong Sup Ihn·Su-Yong Lee·Sean Crowe·Stefan Evans·Marcio de Andrade·Joanna Ptasinski
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Abstract

We study two-photon entangled states for quantum radar cross section (QRCS), which is an extension of a single-photon QRCS formula. Since signal-idler entanglement does not provide any enhancement of the QRCS [Brandsema's PhD Thesis (2017)], we focus on signal-signal entanglement and derive the corresponding biphoton QRCS. We show that it can provide an enhancement over the single-photon QRCS and two-photon separable QRCS, where the performance is evaluated for various two-dimensional target geometries in monostatic/bistatic configurations. Furthermore, using the double-Gaussian approximation, we derive QRCS formula for biphoton states with arbitrary degree of entanglement and compute the resulting scattering patterns.

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Sunghwa Kang, Jihwan Kim, Zaeill Kim, Duk Y. Kim, Yong Sup Ihn, Su-Yong Lee, Sean Crowe, Stefan Evans, Marcio de Andrade, Joanna Ptasinski. 2026-06-04. Quantum Radar Cross Section with two-photon entangled states. https://arxiv.org/abs/2606.05603

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