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arXiv · 2608.10794

Quantum Theory of Third-harmonic Generation in Epsilon-Near-Zero Materials

Sonia Alipour·Riccardo Franchi·Tornike Shubitidze·Smridhi Chawla·Luca Dal Negro·Marco Ornigotti
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Abstract

We present a theoretical framework, based on the Green's tensor quantization method, to describe third-harmonic generation in epsilon-near-zero (ENZ) materials and derive analytical, closed-form solutions for the generation efficiency. We validate our model against experimental measurements of wavelength- and angle-resolved third-harmonic generation efficiency from 30 nm-thin ITO nanolayers at low pump intensity, described under the undepleted pump approximation. Our results provide a local and scalar effective model for quantum nonlinear processes in dispersive and lossy ENZ media, and establishes a simple and reliable framework for investigating a variety of nonlinear optical phenomena with applications to quantum sensing, quantum information, and quantum nondemolition measurements.

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Sonia Alipour, Riccardo Franchi, Tornike Shubitidze, Smridhi Chawla, Luca Dal Negro, Marco Ornigotti. 2026-08-30. Quantum Theory of Third-harmonic Generation in Epsilon-Near-Zero Materials. https://arxiv.org/abs/2608.10794

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