Arrays of magnetic wires created in phase-separating Fe-containing alloys by interference laser irradiation

Abstract

Using the interference of laser beams, we have fabricated the periodic arrays of submicron wires in Fe/C and Fe/Cr thin-film alloys. The array formation is found to arise from iron agglomeration in interference maxima. The dramatic decay of the in-plane magnetic anisotropy was observed in the fabricated arrays with decrease in the interference periodicity down to 170 nm. This decay can rather be explained by transforming the wires into separate granules than a smallness of the temperature modulation at small periodicities. Such an explanation is supported by the electronmicroscopic and ferromagnetic resonance data.

Evidence of Long-Wavelength Collective Excitations in Magnetic Superlattices

“…Our samples are lateral heterostructures patterned directly by laser beams in Fe-based alloyed films [15] and having one-dimensional periodic modulation of the static magnetization M. In the spin excitation spectra of such systems, we find a crossover from the two-frequency (doublet) to single-frequency (singlet) peak, as the orientation of an external magnetic field H is changed with respect to the direction of periodicity. Qualitatively, we explain the observed crossover by the effects of the longwavelength (QD 1) nonevanescent fields [that is, these fields in bulk are given by h ÿ4n mn, where m is the dynamic magnetization and n the unit vector along the direction of propagation].…”

Laser-induced diffusion decomposition in Fe–V thin-film alloys

“…A particular kind of phase transformations that would be very challenging for laser patterning is atomic intermixing in multilayers [15] or, vice versa, phase separation (diffusion decomposition) in alloyed films [13][14][15][16]. Such diffusion processes can be accompanied by a change of the physical properties of the material, leading to the formation of small structures [15].…”

“…There is currently considerable interest to selectively drive phase transformations in solids, with formation of small structures on the solid surface [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. Due to the high productivity and versatility of commercial laser sources, laser-induced surface patterning finds diverse applications in the field of technology [1][2][3].…”

Local magnetostrictive response of small magnetic entities in artificial Fe–Cr composites

“…In the Fe 70 Cr 30 alloys subjected to laser annealing, we revealed arising of a room-temperature ferromagnetic phase, in which the saturation magnetization was close to that in bulk Fe. 4,8 It is believed that by laser annealing, the alloy components mix up in the liquid phase to yield, when cooled, a supersaturated solid solution with a high Curie temperature. 9 In producing small magnetic features, the peculiarity of such processing is that the patterned features strongly depend on the parameters of a heating pulse.…”