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arXiv · 2609.35146

Nonlinear Quantum Optics in Epsilon-Nesar-Zero Nanospheres: a Macroscopic Quantum Electrodynamics Approach

Sonia Alipour·Marco Ornigotti
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Abstract

We present a theoretical framework for handling quantum nonlinear processes in epsilon-near-zero (ENZ_ nano spheres, based on macroscopic quantum electrodynamics and the resonant states (RSs) expansion of the Green's tensor in nano cavities. Using third-harmonic generation (THG) as a case study, we derive analytical expressions for the generation efficiency, and the quantum fluctuations of the generated nonlinear field, as a function of different quantum states of the impinging pump field. Finally, we discuss how to generalise this theoretical framework to arbitrarily quantum nonlinear processes in photonic nanostructures.

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Sonia Alipour, Marco Ornigotti. 2026-09-28. Nonlinear Quantum Optics in Epsilon-Nesar-Zero Nanospheres: a Macroscopic Quantum Electrodynamics Approach. https://arxiv.org/abs/2609.35146

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