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Morphology and magnetic properties of Fe3O 4 nanodot arrays using template-assisted epitaxial growth.

Guan XF, Chen D, Quan ZY, Jiang FX, Deng CH, Gehring GA, Xu XH - Nanoscale Res Lett (2015)

Bottom Line: The calculated nanodot density was as high as 0.18 Tb in.(-2) when D = 40 nm.Results showed that magnetic properties could be tailored through the morphology of nanodots.Therefore, Fe3O4 nanodot arrays may be applied in high-density magnetic storage and spintronic devices.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education and School of Chemistry and Materials Science, Shanxi Normal University, Linfen, 041004, China, guanxiaofen325@163.com.

ABSTRACT
Arrays of epitaxial Fe3O4 nanodots were prepared using laser molecular beam epitaxy (LMBE), with the aid of ultrathin porous anodized aluminum templates. An Fe3O4 film was also prepared using LMBE. Atomic force microscopy and scanning electron microscopy images showed that the Fe3O4 nanodots existed over large areas of well-ordered hexagonal arrays with dot diameters (D) of 40, 70, and 140 nm; height of approximately 20 nm; and inter-dot distances (D int) of 67, 110, and 160 nm. The calculated nanodot density was as high as 0.18 Tb in.(-2) when D = 40 nm. X-ray diffraction patterns indicated that the as-grown Fe3O4 nanodots and the film had good textures of (004) orientation. Both the film and the nanodot arrays exhibited magnetic anisotropy; the anisotropy of the nanoarray weakened with decreasing dot size. The Verwey transition temperature of the film and nanodot arrays with D ≥ 70 nm was observed at around 120 K, similar to that of the Fe3O4 bulk; however, no clear transition was observed from the small nanodot array with D = 40 nm. Results showed that magnetic properties could be tailored through the morphology of nanodots. Therefore, Fe3O4 nanodot arrays may be applied in high-density magnetic storage and spintronic devices.

No MeSH data available.


AFM images of Fe3O4dot array withD = 70 nm.
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Fig2: AFM images of Fe3O4dot array withD = 70 nm.

Mentions: AFM images of the Fe3O4 nanodot array with D of approximately 70 nm and Dint of approximately 115 nm are shown in Figure 2. These images confirm that nanodots have a well-ordered hexagonal arrangement in agreement with the SEM results. Although the nanodots and the film were prepared using the same parameters, the average dot height of Fe3O4 is around 20 nm, which is slightly lower than the thickness (24 nm) of the film. Possibly, some of the atoms cannot arrive at the bottom of the pore, but rather are deposited on the surface of the pore wall and disappeared during the removal of the PAA templates.Figure 2


Morphology and magnetic properties of Fe3O 4 nanodot arrays using template-assisted epitaxial growth.

Guan XF, Chen D, Quan ZY, Jiang FX, Deng CH, Gehring GA, Xu XH - Nanoscale Res Lett (2015)

AFM images of Fe3O4dot array withD = 70 nm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4493851&req=5

Fig2: AFM images of Fe3O4dot array withD = 70 nm.
Mentions: AFM images of the Fe3O4 nanodot array with D of approximately 70 nm and Dint of approximately 115 nm are shown in Figure 2. These images confirm that nanodots have a well-ordered hexagonal arrangement in agreement with the SEM results. Although the nanodots and the film were prepared using the same parameters, the average dot height of Fe3O4 is around 20 nm, which is slightly lower than the thickness (24 nm) of the film. Possibly, some of the atoms cannot arrive at the bottom of the pore, but rather are deposited on the surface of the pore wall and disappeared during the removal of the PAA templates.Figure 2

Bottom Line: The calculated nanodot density was as high as 0.18 Tb in.(-2) when D = 40 nm.Results showed that magnetic properties could be tailored through the morphology of nanodots.Therefore, Fe3O4 nanodot arrays may be applied in high-density magnetic storage and spintronic devices.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education and School of Chemistry and Materials Science, Shanxi Normal University, Linfen, 041004, China, guanxiaofen325@163.com.

ABSTRACT
Arrays of epitaxial Fe3O4 nanodots were prepared using laser molecular beam epitaxy (LMBE), with the aid of ultrathin porous anodized aluminum templates. An Fe3O4 film was also prepared using LMBE. Atomic force microscopy and scanning electron microscopy images showed that the Fe3O4 nanodots existed over large areas of well-ordered hexagonal arrays with dot diameters (D) of 40, 70, and 140 nm; height of approximately 20 nm; and inter-dot distances (D int) of 67, 110, and 160 nm. The calculated nanodot density was as high as 0.18 Tb in.(-2) when D = 40 nm. X-ray diffraction patterns indicated that the as-grown Fe3O4 nanodots and the film had good textures of (004) orientation. Both the film and the nanodot arrays exhibited magnetic anisotropy; the anisotropy of the nanoarray weakened with decreasing dot size. The Verwey transition temperature of the film and nanodot arrays with D ≥ 70 nm was observed at around 120 K, similar to that of the Fe3O4 bulk; however, no clear transition was observed from the small nanodot array with D = 40 nm. Results showed that magnetic properties could be tailored through the morphology of nanodots. Therefore, Fe3O4 nanodot arrays may be applied in high-density magnetic storage and spintronic devices.

No MeSH data available.