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arXiv · 1409.4963

Terahertz Magnetic Modulator based on Magnetically-Clustered Nanoparticles

Mostafa Shalaby·Marco Peccianti·Yavuz Ozturk·Ibraheem Al-Naib·Christoph P. Hauri·Roberto Morandotti
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Abstract

Random orientation of liquid-suspended magnetic nanoparticles (Ferrofluid) gives rise to zero net magnetic orientation. An external magnetic field tends to align them into clusters, leading to a strong linear dichroism on a propagating wave. Using 10 nm-sized Fe3O4, we experimentally realize a polarization-sensitive magnetic modulator operating at terahertz wavelengths. We reached a modulation depth of 66% using a field of 35 mT. The proposed concept offers a solution towards fundamental terahertz magnetic modulators.

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Mostafa Shalaby, Marco Peccianti, Yavuz Ozturk, Ibraheem Al-Naib, Christoph P. Hauri, Roberto Morandotti. 2014-09-17. Terahertz Magnetic Modulator based on Magnetically-Clustered Nanoparticles. https://doi.org/10.1063/1.4898095

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