Room temperature ferromagnetism in Si nanocaps on self-assembled glass beads

• Autorzy: Chi Y. C. , Liou Y.
• Języki publikacji: EN

Abstrakty

EN

Based on self-assembly techniques, Si layers of various thicknesses were deposited on glass bead arrays of various dimensions. The experimental results support the view that the self-assembled glass beads of small sizes (i.e., 10 and 20 nm in diameter), covered with a Si layer below 5 nm in thickness, can induce ferromagnetism. Regularity in the saturation magnetization confirms that the ferromagnetic-like behaviours heavily depend on both the size of the glass beads as well as the thickness of Si nanocaps. Maximum magnetization (750 emu/cm3) was found in the 20 nm glass bead template on which was deposited an ultra-thin 1 nm Si layer. We suggest that the quantum confinement mechanism helps to promote the unpaired electrons, which interact with neighbouring counterparts through the tunnelling effect and, thus, contribute to room temperature ferromagnetism.

Słowa kluczowe

EN

ferromagnetism; nanosphere lithography; quantum confinement; exciton Bohr radius; tunnelling effects

• Wydawca: De Gruyter
• Czasopismo: Materials Science Poland
• Rocznik: 2010
• Tom: Vol. 28, No. 4
• Strony: 823--832
• Opis fizyczny: Bibliogr. 22 poz.

Twórcy

autor

Chi Y. C.

autor

Liou Y.

• Institute of Materials Engineering National Taiwan Ocean University Keelung, 20224 Taiwan Republic of China

Bibliografia

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