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Direct evidence for ferromagnetic spin polarization in gold nanoparticles

Y. Yamamoto·T. Miura·T. Teranishi·M. Miyake·H. Hori·M. Suzuki·N. Kawamura·H. Miyagawa·T. Nakamura·K. Kobayashi
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Abstract

We report the first direct observation of ferromagnetic spin polarization of Au nanoparticles with a mean diameter of 1.9 nm using X-ray magnetic circular dichroism (XMCD). Owing to the element selectivity of XMCD, only the gold magnetization is explored. Magnetization of gold atoms estimated by XMCD shows a good agreement with the results obtained by conventional magnetometry. This result is evidence of intrinsic spin polarization in nano-sized gold.

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Y. Yamamoto, T. Miura, T. Teranishi, M. Miyake, H. Hori, M. Suzuki, N. Kawamura, H. Miyagawa, T. Nakamura, K. Kobayashi. 2004-03-24. Direct evidence for ferromagnetic spin polarization in gold nanoparticles. https://doi.org/10.1103/physrevlett.93.116801

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