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arXiv · 2503.04571

Magnetic Permeability Time-varying Metamaterials at Microwave Frequencies

Toshiyuki Kodama·Nobuaki Kikuchi·Takahiro Chiba·Seigo Ohno·Satoshi Okamoto·Satoshi Tomita
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Abstract

We demonstrate magnetic permeability time-varying metamaterials at GHz frequencies using ferromagnetic permalloy (Ni80Fe20; Py). We observe frequency up and down conversion of 4 GHz microwaves through the metamaterials, which is caused by the temporal modulation of permeability in the Py layer. Moreover, the efficiency of the up-conversion to a higher frequency is much larger than that of the down conversion to a lower frequency. These experimental results are reproduced well via numerical calculation, verifying that the significant up-conversion efficiency is traced back to nonlinear magnetization dynamics in the metamaterials. The present study opens a door to microwave sources toward the 6th-generation mobile communication system, four-dimensional metamaterials with spatio-temporal modulation, and nonlinear spintronics.

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Toshiyuki Kodama, Nobuaki Kikuchi, Takahiro Chiba, Seigo Ohno, Satoshi Okamoto, Satoshi Tomita. 2025-03-15. Magnetic Permeability Time-varying Metamaterials at Microwave Frequencies. https://arxiv.org/abs/2503.04571

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