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arXiv · 1502.04934

Direct Observation of Ferromagnetic State in Gold Nanorods Probed using Electron Spin Resonance Spectroscopy

Yuji Inagaki·Tatsuya Kawae·Natsuko Sakai·Yuta Makihara·Hiroaki Yonemura·Sunao Yamada
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Abstract

X-band electron spin resonance (ESR) spectroscopy has been performed for gold nanorods (AuNRs) of four different sizes covered with a diamagnetic stabilizing component, cetyltrimethylammmonium bromide. The ESR spectra show ferromagnetic features such as hysteresis and resonance field shift, depending on the size of the AuNRs. In addition, the ferromagnetic transition is indicated by an abrupt change in the spectra of the two smallest AuNRs studied. A large g-value in the paramagnetic region suggests that the ferromagnetism in the AuNRs originates from strong spin-orbit interaction.

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Yuji Inagaki, Tatsuya Kawae, Natsuko Sakai, Yuta Makihara, Hiroaki Yonemura, Sunao Yamada. 2015-02-17. Direct Observation of Ferromagnetic State in Gold Nanorods Probed using Electron Spin Resonance Spectroscopy. https://arxiv.org/abs/1502.04934

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