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arXiv · 2601.11411

Hysteresis in the complex nonlinear refractive index of a homogeneous and isotropic medium

Igor Kuzmenko·Y. B. Band·Yshai Avishai·Marek Trippenbach
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Abstract

We calculate the permittivity, $\epsilon(\omega)$, for a medium with a quadratic electro-optic effect, modeling it as a Duffing oscillator. The nonlinear refractive index $n(\omega, E(\omega))$ and the nonlinear absorption coefficient $\alpha(\omega, E(\omega))$ exhibit hysteresis when the light intensity is varied [here $E(\omega)$ is the electric field strength at angular frequency $\omega$], and when the light frequency is varied. $n(\omega, E(\omega))$ can be negative when the resonances in the permittivity and permeability are close to one another.

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Igor Kuzmenko, Y. B. Band, Yshai Avishai, Marek Trippenbach. 2026-01-16. Hysteresis in the complex nonlinear refractive index of a homogeneous and isotropic medium. https://arxiv.org/abs/2601.11411

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