J. Alameda - Academia.edu (original) (raw)
Papers by J. Alameda
Le Journal de Physique Colloques
Applied Physics Letters
Thin perpendicular magnetic anisotropy films between two soft ferromagnetic layers have the nucle... more Thin perpendicular magnetic anisotropy films between two soft ferromagnetic layers have the nuclei for magnetization inversion at the bifurcations of their characteristic stripe domain pattern. The inverted nuclei induce vortex-antivortex pairs in the soft magnetic layers that exhibit a correlated motion extending several lm along the magnetic stripes during magnetization reversal. The sense of motion is completely determined by the topology of the magnetic bifurcations causing vortex-antivortex pairs to propagate in opposite senses depending on their polarities. This is a robust effect that might have practical applications. These findings are based on X-ray microscopy and micromagnetic calculations. Published by AIP Publishing.
Physical Review B, 2015
Spring magnets based on GdCo multilayers have been prepared to study the nucleation and evolution... more Spring magnets based on GdCo multilayers have been prepared to study the nucleation and evolution of interfacial domain walls (iDWs) depending on layer composition and interlayer coupling. GdCo alloy compositions in each layer were chosen so that their net magnetization aligns either with the Gd (Gd 35 Co 65) or Co(Gd 11 Co 89) sublattices. This condition forces an antiparallel arrangement of the layers' net magnetization and leads to nucleation of iDWs above critical magnetic fields whose values are dictated by the interplay between Zeeman and exchange energies. By combining x-ray resonant magnetic scattering with Kerr magnetometry, we provide detailed insight into the nucleation and spatial profile of the iDWs. For strong coupling (GdCo/GdCo bilayer), iDWs are centered at the interface but with asymmetric width depending on each layer magnetization. When interlayer coupling is weakened by introducing a thin Gd interlayer, the exchange spring effect becomes restricted to a lower temperature and field range than observed in the bilayer structure. Due to the ferromagnetic alignment between the high magnetization Gd 35 Co 65 layer and the Gd interlayer, the iDW shrinks and moves into the lower exchange Gd interlayer, causing a reduction of iDW energy.
Le Journal de Physique Colloques, 1988
Magnetic properties of as-prepared (sputtered) and annealed Fe,Sil-, (0.64 5 x 5 0.78) amorphous ... more Magnetic properties of as-prepared (sputtered) and annealed Fe,Sil-, (0.64 5 x 5 0.78) amorphous films
Journal of the Magnetics Society of Japan, 1991
Magnetic, magneto-optical propcrties and Auger depth profiling performed in Ni Y x I-x amorphous ... more Magnetic, magneto-optical propcrties and Auger depth profiling performed in Ni Y x I-x amorphous films are reported. Kerr effect measurements were carried out at both film/air (f/a) and glass/film (fig) interfaces. Anomalous magnetic surface effects on amorphous Ni Y have been 0.91 0.09 detected. We discuss these results and contrast them with those of Co Y thin films. x I-x
ChemInform, 1993
ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Journal de Physique, 1985
Nanotechnology, 2014
Strong asymmetries have been observed in grazing incidence small angle x-ray scattering (GISAXS) ... more Strong asymmetries have been observed in grazing incidence small angle x-ray scattering (GISAXS) in situ patterns obtained from 30 nm-thick nanocrystalline Co films prepared by oblique sputtering (15°-75°off-sample normal). These asymmetries have been qualitatively simulated by a simple model consisting of an ensemble of 8 nm-wide inclined Co nanocolumns. It is found that narrow inclined features appear in the diffuse background resembling those characteristic of faceted systems, which can be used to obtain straightforward non-destructive estimations of buried nanocolumnar grains inclination, even for oblique angles below 45°, when the stronger and broader asymmetric features of the pattern are not yet fully formed. Furthermore, using magneto-optical microscopy, a marked change in the magnetic domain's nucleation and growth process has been observed in the sample prepared at 75°, with the stronger GISAXS asymmetries. Easy axis magnetization reversal starts by a random and homogeneous nucleation of small (∼μm) elongated domains aligned with the nanocolumn's long axis and proceeds through the preferred propagation of head-to-head domain walls (DWs) along the applied field direction. This peculiar magnetic behavior indicates that the strongly anisotropic nanostructuring created by the oblique growth process is equivalent, from a magnetic point of view, to an array of self-assembled buried nanowires. These results show how GISAXS and magneto-optical microscopy can be combined as a powerful tool for correlating the morphology and magnetism of thin nanostructured systems.
Journal of Applied Physics, 2014
Magnetization reversal processes have been studied in hybrid magnetic/superconducting Nd-Co/Nb bi... more Magnetization reversal processes have been studied in hybrid magnetic/superconducting Nd-Co/Nb bilayers by the comparison of out-of-plane magnetic hysteresis loops and superconducting phase diagrams as a function of magnetic layer thickness and of disorder in the magnetic layer induced by a nanostructured copolymer template. A good correlation is found between the regimes corresponding to percolation effects in the superconductor and to the transition from extended to confined superconductivity with the characteristic fields for reverse domain nucleation and fast domain expansion in the magnetic layer, indicating that superconductivity nucleates on the disordered network imprinted on the superconducting layer by the labyrinth domain structure of the magnetic layer. As disorder increases in the magnetic layer, percolation effects disappear from the superconducting transitions in agreement with a more homogeneous magnetization reversal process. V
Physical Review B, 2010
The superconducting and magnetic properties of a-Co x Si 1−x / Nb bilayers have been studied as a... more The superconducting and magnetic properties of a-Co x Si 1−x / Nb bilayers have been studied as a function of Co content in order to analyze the superconducting/ferromagnetic proximity effect in a system with strong disorder in the magnetic layers. As Co atoms become more diluted, the magnetization of the amorphous a-Co x Si 1−x alloy decreases gradually, whereas their resistivity increases and enters in a weak localization regime. The superconducting transition temperatures of the a-Co x Si 1−x / Nb bilayers follow a decreasing trend as Co content is reduced, reaching the lowest value at the boundary between the ferromagnetic-nonmagnetic amorphous phases. These results can be understood in terms of the increase in interface transparency together with the changes in the spin-flip scattering term as magnetic disorder increases and the amorphous a-Co x Si 1−x layers loose their magnetic character.
physica status solidi (a), 2006
The effect of temperature on the magnetic properties of antiferromagnetically coupled amorphous C... more The effect of temperature on the magnetic properties of antiferromagnetically coupled amorphous Co 0.74 Si 0.25 /Si multilayers has been investigated by Magneto-Optical Transverse Kerr Effect and Superconducting Quantum Interference Device. The studied temperature range has been varied between 5 K (15 K for Kerr loops) and room temperature. The results show that the Curie temperature of the multilayers is close to room temperature and that the antiferromagnetic exchange coupling can only be detected at temperatures close to the Curie temperature. When the temperature is decreased, the coercive field of the single films composing the multilayer increases, masking the antiferromagnetic coupling below 250 K. Field-Cooling and Zero-Field-Cooling measurements suggest the presence of a small superparamagnetic contribution.
physica status solidi (a), 2006
The characteristics of the Bloch walls across the thickness that appear at high fields in Gd 0.28... more The characteristics of the Bloch walls across the thickness that appear at high fields in Gd 0.28 Co 0.72 / Gd 0.12 Co 0.88 exchange coupled double layers have been studied by transverse Kerr effect. From the modelling of the magneto-optical response the wall thickness is obtained as a function of magnetic field H and temperature. Wall thickness is found to decrease as H-1/2 in agreement with theoretical predictions. On the other hand, the thickness of the wall when it is created at the interface increases linearly with temperature.
Physica Status Solidi (a), 1984
ABSTRACT Transverse biased initial susceptibility measurements are performed in sputtered FexSi1−... more ABSTRACT Transverse biased initial susceptibility measurements are performed in sputtered FexSi1−x films (0.85 ≧ x > 0.60; thickness: 30 to 300 nm). Both χt(0) and χt(π/2) are measured. The deduced structure constant S in amorphous FexSi1−x; thin films (0.75 ≧ x > 0.60 and thickness in the range 30 to 100 nm) is S = 6 × 10−5 J/m2. The physical origins of the related local anisotropies are discussed in terms of the random anisotropy model of amorphous magnetism. From 8, values of local anisotropy: 105 J/m3 < Kloc ≦ 106 J/m3 related with correlation lengths: 2 nm > d ≧ ≧ 0.25 nm are deduced.Nous avons étudié les propriétés magnetiques des couches minces amorphes de FexSi1−x (0,85 ≧ ≧ x > 0,6; épaisseur : 30 à 300 nm) à partir des mesures de la susceptibilité transversale. On a mesuré χ(0) et χ(π/2). Les résultats expérimentaux impliquent une valeur moyenne pour la constant de structure; S = 6 × 10−5 J/m2, pour des couches dans les intervalles de composition et d'épaisseur: 0,75 ≧ x > 0,6 et 30 à 100 nm. Une discussion sur l'origine physique des anisotropies locales qui peut justifier ces résultats, est faite en tenant compte des modèles d'anisotropie aléatoire ultilisés dans le magnétisme amorphe. On obtient: 105 J/m3 < Kloc ≦ 106 J/m3 pour des longeurs de correlation: 2 nm > d ≧ 0,25 nm
Physica B: Condensed Matter, 2001
We report experimental measurements and a micromagnetic model of amorphous thin films with an out... more We report experimental measurements and a micromagnetic model of amorphous thin films with an out-of-plane uniaxial anisotropy: KN. There is a renewed interest on this kind of films, having 0≪Q(KN/2πMS2)⩽1, because of its applications in magnetic devices: these films show characteristics hysteresis loops with a high remanent state (in our case: 0.8MS at room temperature). Bulk measurements of the associated weak stripe domains structure, when the temperature is changed between 375K⩾T⩾200K, are presented. We have developed a 2-D model of the μ*-effect: a tilting of the magnetization near the surface of the sample. 1-D models, which give a phenomenological treatment to the μ*-effect, are compared to our model and critically analyzed. Finally, we present transverse biased initial susceptibility (TBIS) measurements: a simple and well-developed technique used to quantify anisotropy fields.
Nanotechnology, 2004
Diluted arrays of antidots have been patterned by electron beam lithography and an etching proces... more Diluted arrays of antidots have been patterned by electron beam lithography and an etching process on amorphous Co-Si films of well defined uniaxial anisotropy. The analysis of the angular dependence of the hysteresis loops shows that the antidot arrays present a similar uniaxial anisotropy to the unpatterned film, and that the main effect of patterning for this small antidot density
Nanotechnology, 2003
... Phys. 87 824 [11] Jaccard Y, Guittienne Ph, Kelly D, Wegrowe JE and Ansermet J-Ph 2000 Phys. ... more ... Phys. 87 824 [11] Jaccard Y, Guittienne Ph, Kelly D, Wegrowe JE and Ansermet J-Ph 2000 Phys. Rev. B 62 1141 [12] Martın JI, Jaccard Y, Hoffmann A, Nogués J, George JM, Vicent JL and Schuller IK 1998 J. Appl. Phys. 84 411 [13] Martın JI, Vélez M, Morales R, Alameda JM ...
Microelectronic Engineering, 2007
... a Departamento de Física, Facultad de Ciencias, Universidad de Oviedo, c/Calvo Sotelo s/n, 33... more ... a Departamento de Física, Facultad de Ciencias, Universidad de Oviedo, c/Calvo Sotelo s/n, 33007 Oviedo, Spain. ... [2] MA McCord and MJ Rooks In: P. Rai-Choudhury, Editor, Handbook of Microlithography, Micromachining and Microfabrication vol. ...
![Research paper thumbnail of Magnetic properties of amorphous Co[sub 0.74]Si[sub 0.26]∕Si multilayers with different numbers of periods](https://attachments.academia-assets.com/74360211/thumbnails/1.jpg)
](Low Temperature Physics, 2010
Two sets of ͓Co 0.74 Si 0.26 ͑5 nm͒ / Si͑s͔͒ n amorphous films were prepared by magnetron sputter... more Two sets of ͓Co 0.74 Si 0.26 ͑5 nm͒ / Si͑s͔͒ n amorphous films were prepared by magnetron sputtering: one in the form of multilayers with the Si spacer thickness s fixed at 3 nm, and the number n of periods varying from 1 to 10 and the other with only two periods and s varying from 3 to 24 nm ͑trilayers͒. In both sets, the Co 0.74 Si 0.26 layer thickness t was fixed at 5 nm. All the samples except the one with s = 24 nm manifest antiferromagnetic coupling. Their magnetic properties at room temperature were probed using the magnetooptical transverse Kerr effect ͑MOTKE͒ and ferromagnetic resonance ͑FMR͒. The relative increase in the saturation magnetization M s ͑for trilayers, relative to a structure with s = 24 nm; for multilayers, relative to the single-layer struc-ture͒ determined from the FMR measurements was compared with the exchange coupling strength H J AF obtained from the MOTKE studies. The dependences of H J AF and M s on n and s were found to be very similar to each other. Possible mechanisms of this similarity are discussed.
Journal of Physics: Condensed Matter, 2007
... Matter 18 6987 [24] Chang HW, Tsay JS, Hung YC, Yuan FT, Chan WY, Su WB, Chang CS and Yao YD ... more ... Matter 18 6987 [24] Chang HW, Tsay JS, Hung YC, Yuan FT, Chan WY, Su WB, Chang CS and Yao YD 2007 J. Appl. Phys. 101 09D124 [25] Abhaya S, Venugopal Rao G, Kalavathi S, Sastry VS and Amarendra G 2006 Surf. Sci. ...
Le Journal de Physique Colloques
Applied Physics Letters
Thin perpendicular magnetic anisotropy films between two soft ferromagnetic layers have the nucle... more Thin perpendicular magnetic anisotropy films between two soft ferromagnetic layers have the nuclei for magnetization inversion at the bifurcations of their characteristic stripe domain pattern. The inverted nuclei induce vortex-antivortex pairs in the soft magnetic layers that exhibit a correlated motion extending several lm along the magnetic stripes during magnetization reversal. The sense of motion is completely determined by the topology of the magnetic bifurcations causing vortex-antivortex pairs to propagate in opposite senses depending on their polarities. This is a robust effect that might have practical applications. These findings are based on X-ray microscopy and micromagnetic calculations. Published by AIP Publishing.
Physical Review B, 2015
Spring magnets based on GdCo multilayers have been prepared to study the nucleation and evolution... more Spring magnets based on GdCo multilayers have been prepared to study the nucleation and evolution of interfacial domain walls (iDWs) depending on layer composition and interlayer coupling. GdCo alloy compositions in each layer were chosen so that their net magnetization aligns either with the Gd (Gd 35 Co 65) or Co(Gd 11 Co 89) sublattices. This condition forces an antiparallel arrangement of the layers' net magnetization and leads to nucleation of iDWs above critical magnetic fields whose values are dictated by the interplay between Zeeman and exchange energies. By combining x-ray resonant magnetic scattering with Kerr magnetometry, we provide detailed insight into the nucleation and spatial profile of the iDWs. For strong coupling (GdCo/GdCo bilayer), iDWs are centered at the interface but with asymmetric width depending on each layer magnetization. When interlayer coupling is weakened by introducing a thin Gd interlayer, the exchange spring effect becomes restricted to a lower temperature and field range than observed in the bilayer structure. Due to the ferromagnetic alignment between the high magnetization Gd 35 Co 65 layer and the Gd interlayer, the iDW shrinks and moves into the lower exchange Gd interlayer, causing a reduction of iDW energy.
Le Journal de Physique Colloques, 1988
Magnetic properties of as-prepared (sputtered) and annealed Fe,Sil-, (0.64 5 x 5 0.78) amorphous ... more Magnetic properties of as-prepared (sputtered) and annealed Fe,Sil-, (0.64 5 x 5 0.78) amorphous films
Journal of the Magnetics Society of Japan, 1991
Magnetic, magneto-optical propcrties and Auger depth profiling performed in Ni Y x I-x amorphous ... more Magnetic, magneto-optical propcrties and Auger depth profiling performed in Ni Y x I-x amorphous films are reported. Kerr effect measurements were carried out at both film/air (f/a) and glass/film (fig) interfaces. Anomalous magnetic surface effects on amorphous Ni Y have been 0.91 0.09 detected. We discuss these results and contrast them with those of Co Y thin films. x I-x
ChemInform, 1993
ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Journal de Physique, 1985
Nanotechnology, 2014
Strong asymmetries have been observed in grazing incidence small angle x-ray scattering (GISAXS) ... more Strong asymmetries have been observed in grazing incidence small angle x-ray scattering (GISAXS) in situ patterns obtained from 30 nm-thick nanocrystalline Co films prepared by oblique sputtering (15°-75°off-sample normal). These asymmetries have been qualitatively simulated by a simple model consisting of an ensemble of 8 nm-wide inclined Co nanocolumns. It is found that narrow inclined features appear in the diffuse background resembling those characteristic of faceted systems, which can be used to obtain straightforward non-destructive estimations of buried nanocolumnar grains inclination, even for oblique angles below 45°, when the stronger and broader asymmetric features of the pattern are not yet fully formed. Furthermore, using magneto-optical microscopy, a marked change in the magnetic domain's nucleation and growth process has been observed in the sample prepared at 75°, with the stronger GISAXS asymmetries. Easy axis magnetization reversal starts by a random and homogeneous nucleation of small (∼μm) elongated domains aligned with the nanocolumn's long axis and proceeds through the preferred propagation of head-to-head domain walls (DWs) along the applied field direction. This peculiar magnetic behavior indicates that the strongly anisotropic nanostructuring created by the oblique growth process is equivalent, from a magnetic point of view, to an array of self-assembled buried nanowires. These results show how GISAXS and magneto-optical microscopy can be combined as a powerful tool for correlating the morphology and magnetism of thin nanostructured systems.
Journal of Applied Physics, 2014
Magnetization reversal processes have been studied in hybrid magnetic/superconducting Nd-Co/Nb bi... more Magnetization reversal processes have been studied in hybrid magnetic/superconducting Nd-Co/Nb bilayers by the comparison of out-of-plane magnetic hysteresis loops and superconducting phase diagrams as a function of magnetic layer thickness and of disorder in the magnetic layer induced by a nanostructured copolymer template. A good correlation is found between the regimes corresponding to percolation effects in the superconductor and to the transition from extended to confined superconductivity with the characteristic fields for reverse domain nucleation and fast domain expansion in the magnetic layer, indicating that superconductivity nucleates on the disordered network imprinted on the superconducting layer by the labyrinth domain structure of the magnetic layer. As disorder increases in the magnetic layer, percolation effects disappear from the superconducting transitions in agreement with a more homogeneous magnetization reversal process. V
Physical Review B, 2010
The superconducting and magnetic properties of a-Co x Si 1−x / Nb bilayers have been studied as a... more The superconducting and magnetic properties of a-Co x Si 1−x / Nb bilayers have been studied as a function of Co content in order to analyze the superconducting/ferromagnetic proximity effect in a system with strong disorder in the magnetic layers. As Co atoms become more diluted, the magnetization of the amorphous a-Co x Si 1−x alloy decreases gradually, whereas their resistivity increases and enters in a weak localization regime. The superconducting transition temperatures of the a-Co x Si 1−x / Nb bilayers follow a decreasing trend as Co content is reduced, reaching the lowest value at the boundary between the ferromagnetic-nonmagnetic amorphous phases. These results can be understood in terms of the increase in interface transparency together with the changes in the spin-flip scattering term as magnetic disorder increases and the amorphous a-Co x Si 1−x layers loose their magnetic character.
physica status solidi (a), 2006
The effect of temperature on the magnetic properties of antiferromagnetically coupled amorphous C... more The effect of temperature on the magnetic properties of antiferromagnetically coupled amorphous Co 0.74 Si 0.25 /Si multilayers has been investigated by Magneto-Optical Transverse Kerr Effect and Superconducting Quantum Interference Device. The studied temperature range has been varied between 5 K (15 K for Kerr loops) and room temperature. The results show that the Curie temperature of the multilayers is close to room temperature and that the antiferromagnetic exchange coupling can only be detected at temperatures close to the Curie temperature. When the temperature is decreased, the coercive field of the single films composing the multilayer increases, masking the antiferromagnetic coupling below 250 K. Field-Cooling and Zero-Field-Cooling measurements suggest the presence of a small superparamagnetic contribution.
physica status solidi (a), 2006
The characteristics of the Bloch walls across the thickness that appear at high fields in Gd 0.28... more The characteristics of the Bloch walls across the thickness that appear at high fields in Gd 0.28 Co 0.72 / Gd 0.12 Co 0.88 exchange coupled double layers have been studied by transverse Kerr effect. From the modelling of the magneto-optical response the wall thickness is obtained as a function of magnetic field H and temperature. Wall thickness is found to decrease as H-1/2 in agreement with theoretical predictions. On the other hand, the thickness of the wall when it is created at the interface increases linearly with temperature.
Physica Status Solidi (a), 1984
ABSTRACT Transverse biased initial susceptibility measurements are performed in sputtered FexSi1−... more ABSTRACT Transverse biased initial susceptibility measurements are performed in sputtered FexSi1−x films (0.85 ≧ x > 0.60; thickness: 30 to 300 nm). Both χt(0) and χt(π/2) are measured. The deduced structure constant S in amorphous FexSi1−x; thin films (0.75 ≧ x > 0.60 and thickness in the range 30 to 100 nm) is S = 6 × 10−5 J/m2. The physical origins of the related local anisotropies are discussed in terms of the random anisotropy model of amorphous magnetism. From 8, values of local anisotropy: 105 J/m3 < Kloc ≦ 106 J/m3 related with correlation lengths: 2 nm > d ≧ ≧ 0.25 nm are deduced.Nous avons étudié les propriétés magnetiques des couches minces amorphes de FexSi1−x (0,85 ≧ ≧ x > 0,6; épaisseur : 30 à 300 nm) à partir des mesures de la susceptibilité transversale. On a mesuré χ(0) et χ(π/2). Les résultats expérimentaux impliquent une valeur moyenne pour la constant de structure; S = 6 × 10−5 J/m2, pour des couches dans les intervalles de composition et d'épaisseur: 0,75 ≧ x > 0,6 et 30 à 100 nm. Une discussion sur l'origine physique des anisotropies locales qui peut justifier ces résultats, est faite en tenant compte des modèles d'anisotropie aléatoire ultilisés dans le magnétisme amorphe. On obtient: 105 J/m3 < Kloc ≦ 106 J/m3 pour des longeurs de correlation: 2 nm > d ≧ 0,25 nm
Physica B: Condensed Matter, 2001
We report experimental measurements and a micromagnetic model of amorphous thin films with an out... more We report experimental measurements and a micromagnetic model of amorphous thin films with an out-of-plane uniaxial anisotropy: KN. There is a renewed interest on this kind of films, having 0≪Q(KN/2πMS2)⩽1, because of its applications in magnetic devices: these films show characteristics hysteresis loops with a high remanent state (in our case: 0.8MS at room temperature). Bulk measurements of the associated weak stripe domains structure, when the temperature is changed between 375K⩾T⩾200K, are presented. We have developed a 2-D model of the μ*-effect: a tilting of the magnetization near the surface of the sample. 1-D models, which give a phenomenological treatment to the μ*-effect, are compared to our model and critically analyzed. Finally, we present transverse biased initial susceptibility (TBIS) measurements: a simple and well-developed technique used to quantify anisotropy fields.
Nanotechnology, 2004
Diluted arrays of antidots have been patterned by electron beam lithography and an etching proces... more Diluted arrays of antidots have been patterned by electron beam lithography and an etching process on amorphous Co-Si films of well defined uniaxial anisotropy. The analysis of the angular dependence of the hysteresis loops shows that the antidot arrays present a similar uniaxial anisotropy to the unpatterned film, and that the main effect of patterning for this small antidot density
Nanotechnology, 2003
... Phys. 87 824 [11] Jaccard Y, Guittienne Ph, Kelly D, Wegrowe JE and Ansermet J-Ph 2000 Phys. ... more ... Phys. 87 824 [11] Jaccard Y, Guittienne Ph, Kelly D, Wegrowe JE and Ansermet J-Ph 2000 Phys. Rev. B 62 1141 [12] Martın JI, Jaccard Y, Hoffmann A, Nogués J, George JM, Vicent JL and Schuller IK 1998 J. Appl. Phys. 84 411 [13] Martın JI, Vélez M, Morales R, Alameda JM ...
Microelectronic Engineering, 2007
... a Departamento de Física, Facultad de Ciencias, Universidad de Oviedo, c/Calvo Sotelo s/n, 33... more ... a Departamento de Física, Facultad de Ciencias, Universidad de Oviedo, c/Calvo Sotelo s/n, 33007 Oviedo, Spain. ... [2] MA McCord and MJ Rooks In: P. Rai-Choudhury, Editor, Handbook of Microlithography, Micromachining and Microfabrication vol. ...
Low Temperature Physics, 2010
Two sets of ͓Co 0.74 Si 0.26 ͑5 nm͒ / Si͑s͔͒ n amorphous films were prepared by magnetron sputter... more Two sets of ͓Co 0.74 Si 0.26 ͑5 nm͒ / Si͑s͔͒ n amorphous films were prepared by magnetron sputtering: one in the form of multilayers with the Si spacer thickness s fixed at 3 nm, and the number n of periods varying from 1 to 10 and the other with only two periods and s varying from 3 to 24 nm ͑trilayers͒. In both sets, the Co 0.74 Si 0.26 layer thickness t was fixed at 5 nm. All the samples except the one with s = 24 nm manifest antiferromagnetic coupling. Their magnetic properties at room temperature were probed using the magnetooptical transverse Kerr effect ͑MOTKE͒ and ferromagnetic resonance ͑FMR͒. The relative increase in the saturation magnetization M s ͑for trilayers, relative to a structure with s = 24 nm; for multilayers, relative to the single-layer struc-ture͒ determined from the FMR measurements was compared with the exchange coupling strength H J AF obtained from the MOTKE studies. The dependences of H J AF and M s on n and s were found to be very similar to each other. Possible mechanisms of this similarity are discussed.
Journal of Physics: Condensed Matter, 2007
... Matter 18 6987 [24] Chang HW, Tsay JS, Hung YC, Yuan FT, Chan WY, Su WB, Chang CS and Yao YD ... more ... Matter 18 6987 [24] Chang HW, Tsay JS, Hung YC, Yuan FT, Chan WY, Su WB, Chang CS and Yao YD 2007 J. Appl. Phys. 101 09D124 [25] Abhaya S, Venugopal Rao G, Kalavathi S, Sastry VS and Amarendra G 2006 Surf. Sci. ...