Magnetic anisotropy of bcc Co onFeCu3(001)

Abstract

Single crystalline body-centered-cubic ͑bcc͒ Co films were achieved on FeCu 3 buffer layer by molecularbeam epitaxy. Fourfold symmetric magnetic hysteresis loops for bcc Co were obtained unambiguously with the easy axes along Co͗110͘. The in-plane uniaxial anisotropy is significantly reduced by FeCu 3 buffer layer. The magnetocrystalline anisotropy constant of bcc Co was further determined to be −1.0ϫ 10 5 erg/ cm 3 by rotational-magneto-optical Kerr effect. Hexagonal-close-packed Co, which would contribute an effective positive K 1 , appeared on top of bcc Co when the film thickness was beyond 0.9 nm. As a result, the magnetocrystalline anisotropy constant of the whole system switched from negative to positive with increasing film thickness.

Four-fold magnetic anisotropy in a Co film on MgO(001)

“…The signal of K 4: in bcc Co films is a controversial subject involving the interplay between the magnetocrystalline and the surface/interface contributions for the anisotropy and the mixture of crystalline phases [13,34]. Nevertheless, in sample F1 we can say that the four-fold contribution attributed to the magnetocrystalline anisotropy is clearly dominant over the uniaxial one, and the whole set of results indicate a bct film with in-plane /1 1 0S easy axes.…”

Syntheses and Properties of Metal Nanomaterials with Novel Crystal Phases

“…[152] Copyright 2006, American Chemical Society. [111][112][113][114][115] thermal decomposition nanoparticles [86,[118][119][120][121] polyol reduction nanoparticles [116,117] microfluidic synthesis nanoparticles [129] template-assisted calcination hollow spheres [110] reduction of CoO hollow nanoparallelepipeds [122] sputtering nanoparticles [108] reducing flame spray synthesis nanoparticles [109] ε thermal decomposition nanoparticles [17,20,107,121,[124][125][126][127][128] wet-chemical reduction/polyol reduction nanoparticles [106] microfluidic synthesis nanoparticles [129] bcc physical vapor deposition thin films [132][133][134][135] wet-chemical reduction nanoparticles [136] Ni hcp polyol method nanoparticles [116,140,141] wet-chemical reduction nanoparticles, hourglassshaped nanocrystals [139,[145][146][147][148][149]…”

“…Similar to the bcc-Pd films prepared on W substrates via PVD, the bcc-Co films also contain strains and defects and their thickness is very thin (below 5 nm), but the substrates used for bcc-Co are more diverse, including GaAs (110), [132] TiAl (010), [133] Pt (001), [134] and FeCu 3 (001). [135] Although it is very rare, bcc-Co nanoparticles have also been synthesized by wet-chemical reduction in Al 2 O 3 matrix, [136] which have an average diameter of 2-5 nm and showed the size effect on the existence of metastable phase based on rational calculations.…”

The anomalous Hall effect in epitaxial face-centered-cubic cobalt films

“…There have been many works on the epitaxial growth of Co [16][17][18][19][20], but the growth of fcc Co(001) on an insulating substrate which is suitable for in-plane transport measurement is still lacking. We have achieved production of an insulating template for fcc Co(001) film by the growth of 0.8 nm Cu on MgO(001) with post-annealing at 420 • C for 30 min.…”