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arXiv · 2603.12923

Electronics-free, ultra-low-power, wearable sensor chip for high-frequency electromagnetic field detection

Abdul Mohizin·Leon Abelmann·Baeckkyoung Sung
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Abstract

High-frequency electromagnetic fields (EMFs) are increasingly recognized either as environmental risk factors or as tools for electromagnetic attacks, which are difficult to detect in situ. Existing high-frequency EMF sensors face significant limitations related to structural simplicity, integration with mobile technology, and low energy consumption. To address these challenges, we propose a novel sensor concept based on a magnetically hybridized liquid crystal (LC) microdevice. The hybrid LC chip is designed to exhibit an optical response to external radio-frequency fields without the need for electronic components or an external power supply, relying solely on ambient light. Both sides of the chip are covered with polymer-based crossed polarizer films. The chip is filled with flexible matrices containing thermotropic LCs, such as the rod-like 4-cyano-4'-pentylbiphenyl, into which a network of thin ferromagnetic wires is embedded. The resulting field-responsive LC microdisplay operates via a simple magnetothermal mechanism, and its optical response is sufficiently strong to be visible to the naked eye.

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Abdul Mohizin, Leon Abelmann, Baeckkyoung Sung. 2026-03-13. Electronics-free, ultra-low-power, wearable sensor chip for high-frequency electromagnetic field detection. https://arxiv.org/abs/2603.12923

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