Synthesis, Structure, and Magnetic Properties of an Al2O3/Ge-p/Al2O3/Co Thin-Film System

Abstract—Structural and magnetic measurements are made of an Al2O3/Ge-p/Al2O3/Co thin-film system. The structure is synthesized via ion-plasma deposition and can be used as a tunnel heterostructure. The dependences of the magnetic properties of cobalt on the rate of its deposition and the rates of deposition of preceding layers are established

Temperature- and field-induced transformation of the magnetic state in Co2.5Ge0.5BO5

A tetravalent-substituted cobalt ludwigite Co2.5Ge0.5BO5 has been synthesized using the flux method. The compound undergoes two magnetic transitions: a long-range antiferromagnetic transition at TN1 = 84 K and a metamagnetic one at TN2 = 36 K. The sample-oriented magnetization measurements revealed a fully compensated magnetic moment along the a- and c-axes and an uncompensated one along the b-axis leading to high uniaxial anisotropy. A field-induced enhancement of the ferromagnetic correlations at TN2 is observed in specific heat measurements. The DFT+GGA calculation predicts the spin configuration of (↑↓↓↑) as a ground state with a magnetic moment of 1.37 μB/f.u. The strong hybridization of Ge(4s, 4p) with O (2p) orbitals resulting from the high electronegativity of Ge4+ is assumed to cause an increase in the interlayer interaction, contributing to the long-range magnetic order. The effect of two super–superexchange pathways Co2+-O-B-O-Co2+ and Co2+-O-M4-O-Co2+ on the magnetic state is discussed.This work has been financed by the Russian Foundation for Basic Research (project no. 20-02-00559). The authors acknowledge financial support from the Spanish Agencia Estatal de Investigación, through projects MAT2017-83468-R (AEI/FEDER, UE) and PID2020-115159GB-I00/AEI/10.13039/501100011033, the Aragonese project RASMIA E12_20R (co-funded by Fondo Social Europeo), and of the European Union FEDER (ES).Peer reviewe

Synthesis and Magnetic Properties of [(CoP)soft/NiP/(CoP)hard/NiP]n Films

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала.Magnetic interactions in the Co-Ni-P multilayers consisting of alternating magnetically soft and magnetically hard layers are experimentally investigated. The variation in the shape of magnetization loop at the conjugation of magnetically soft and magnetically hard layers and the saturation field oscillations with varying number of layer pairs are established. It is demonstrated that insertion of a nonmagnetic spacer significantly affects magnetization reversal in the structure. It is concluded that in studying the interlayer coupling it is necessary to take into account the biquadratic interaction. В работе представлены результаты экспериментальных исследований магнитных взаимодействий многослойных пленок в системе Co-Ni-P, когда один из слоев является магнитомягким, а другой магнитожестким. Обнаружены изменение формы петли намагничивания при сопряжении магнитомягкого и магнитожесткого слоев, и осцилляция поля насыщения в зависимости от числа пар слоев. Введение немагнитной прослойки существенно изменяет процесс перемагничивания структуры. Делается вывод о необходимости учета биквадратичного взаимодействия при рассмотрении межслоевых взаимодействий

Synthesis and Magnetic Properties of [(CoP)soft/NiP/(CoP)hard/NiP]n Films

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала.Magnetic interactions in the Co-Ni-P multilayers consisting of alternating magnetically soft and magnetically hard layers are experimentally investigated. The variation in the shape of magnetization loop at the conjugation of magnetically soft and magnetically hard layers and the saturation field oscillations with varying number of layer pairs are established. It is demonstrated that insertion of a nonmagnetic spacer significantly affects magnetization reversal in the structure. It is concluded that in studying the interlayer coupling it is necessary to take into account the biquadratic interaction. В работе представлены результаты экспериментальных исследований магнитных взаимодействий многослойных пленок в системе Co-Ni-P, когда один из слоев является магнитомягким, а другой магнитожестким. Обнаружены изменение формы петли намагничивания при сопряжении магнитомягкого и магнитожесткого слоев, и осцилляция поля насыщения в зависимости от числа пар слоев. Введение немагнитной прослойки существенно изменяет процесс перемагничивания структуры. Делается вывод о необходимости учета биквадратичного взаимодействия при рассмотрении межслоевых взаимодействий

Magnetic properties of Fe-Bi films

In the paper the results of experimental studies of film structures in the Fe-Bi system are presented. By the method of electron magnetic resonance, it is shown that for bilayer structures the magnetic state depends on the order of deposition of the magnetic and non-magnetic layers. In the three-layer structures, the effect of exchange bias was found, the magnitude of that depends on the thickness of the bismuth layer. © Published under licence by IOP Publishing Ltd

Magnetic resonance in FeNi/Bi/FeNi films

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала.The magnetic resonance in FeNi/Bi/FeNi trilayer films with nonmagnetic semimetal spacer has been experimentally studied. It is found that the microwave absorption spectrum of samples has a complicated shape dependent on the nonmagnetic spacer thickness. In the interval of Bi layer thicknesses within 3–15 nm, the interlayer coupling has an antiferromagnetic character. © 2015, Pleiades Publishing, Ltd