Influence of magnetic field and ferromagnetic film thickness on domain pattern transfer in multiferroic heterostructures

Ferromagnetic film can be a matrix for recording information with the help of magnetic moments of electrons. The study of the processes of changing the magnetic structure in an electron-transmission microscope makes it possible to investigate micro magnetic phenomena. In this paper, we investigate the interaction between the vertices of neighboring regions. It is shown how the magnetic structure of the vertices of the domains changes as they approach each other with the help of an increasing constant magnetic field applied along the axis of easy magnetization. The distance was measured between the vertices of the domains. The schemes of distribution of the magnetization vectors between interacting vertices are shown. These schemes are made from experimental images of the magnetic structure. The distances between domain vertices and domain walls were compared on the basis of experimental data. The film thickness is 50 nm; the structure is Ni0.83-Fe0.17. The films were obtained by the method proposed by us. From the experimental results it follows that the interaction of the domain walls is observed at a distance of 20 microns and the interaction of the domain vertices is manifested at a distance of 100 μm.

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Size Dependence of Domain Pattern Transfer in Multiferroic Heterostructures

Physical Review Letters ◽

10.1103/physrevlett.112.017201 ◽

2014 ◽

Vol 112 (1) ◽

Cited By ~ 22

Author(s):

Kévin J. A. Franke ◽

Diego López González ◽

Sampo J. Hämäläinen ◽

Sebastiaan van Dijken

Keyword(s):

Size Dependence ◽

Pattern Transfer ◽

Domain Pattern ◽

Multiferroic Heterostructures

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Thermoelectric Power in Quantum Confined Bismuth Under Classically Large Magnetic Field

MRS Proceedings ◽

10.1557/proc-216-465 ◽

1990 ◽

Vol 216 ◽

Cited By ~ 6

Author(s):

Kamakhya P. Ghatak ◽

S. N. Biswas

Keyword(s):

Magnetic Field ◽

Quantum Dots ◽

Quantum Well ◽

Film Thickness ◽

Quantum Wells ◽

Thermoelectric Power ◽

Large Magnetic Field ◽

Quantum Well Wires ◽

Electron Dispersion ◽

Theoretical Results

ABSTRACTIn this paper we studied the thermoelectric power under classically large magnetic field (TPM) in quantum wells (QWs), quantum well wires (QWWS) and quantum dots (QDs) of Bi by formulating the respective electron dispersion laws. The TPM increases with increasing film thickness in an oscillatory manner in all the cases. The TPM in QD is greatest and the least for quantum wells respectively. The theoretical results are in agreement with the experimental observations as reported elsewhere.

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Controllable field-free switching of perpendicular magnetization through bulk spin-orbit torque in symmetry-broken ferromagnetic films

Nature Communications ◽

10.1038/s41467-021-22819-4 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Xuejie Xie ◽

Xiaonan Zhao ◽

Yanan Dong ◽

Xianlin Qu ◽

Kun Zheng ◽

...

Keyword(s):

Magnetic Field ◽

Domain Walls ◽

Single Layer ◽

Ferromagnetic Film ◽

Effective Field ◽

Composition Gradient ◽

Spin Orbit ◽

Interlayer Exchange Coupling ◽

Magnetization Switching ◽

Perpendicular Magnetization

AbstractProgrammable magnetic field-free manipulation of perpendicular magnetization switching is essential for the development of ultralow-power spintronic devices. However, the magnetization in a centrosymmetric single-layer ferromagnetic film cannot be switched directly by passing an electrical current in itself. Here, we demonstrate a repeatable bulk spin-orbit torque (SOT) switching of the perpendicularly magnetized CoPt alloy single-layer films by introducing a composition gradient in the thickness direction to break the inversion symmetry. Experimental results reveal that the bulk SOT-induced effective field on the domain walls leads to the domain walls motion and magnetization switching. Moreover, magnetic field-free perpendicular magnetization switching caused by SOT and its switching polarity (clockwise or counterclockwise) can be reversibly controlled in the IrMn/Co/Ru/CoPt heterojunctions based on the exchange bias and interlayer exchange coupling. This unique composition gradient approach accompanied with electrically controllable SOT magnetization switching provides a promising strategy to access energy-efficient control of memory and logic devices.

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VOLTAGE CONTROL OF MAGNETISM IN MULTIFERROIC HETEROSTRUCTURES AND DEVICES

SPIN ◽

10.1142/s2010324712400048 ◽

2012 ◽

Vol 02 (03) ◽

pp. 1240004 ◽

Cited By ~ 200

Author(s):

NIAN X. SUN ◽

GOPALAN SRINIVASAN

Keyword(s):

Magnetic Field ◽

Communication Systems ◽

Recent Progress ◽

Phase Shifters ◽

Ultra Wideband ◽

Superior Performance ◽

Microwave Devices ◽

Multiferroic Materials ◽

Multiferroic Heterostructures ◽

Rf Microwave

Multiferroic materials and devices have attracted intensified recent interests due to the demonstrated strong magnetoelectric (ME) coupling in new multiferroic materials and devices with unique functionalities and superior performance characteristics. Strong ME coupling has been demonstrated in a variety of multiferroic heterostructures, including bulk magnetic on ferro/piezoelectric multiferroic heterostructures, magnetic film on ferro/piezoelectric slab multiferroic heterostructures, thin film multiferroic heterostructures, etc. Different multiferroic devices have been demonstrated, which include magnetic sensors, energy harvesters, and voltage tunable multiferroic RF/microwave devices which are compact, lightweight, and power efficient. In this progress report, we cover the most recent progress on multiferroic heterostructures and devices with a focus on voltage tunable multiferroic heterostructures and devices with strong converse ME coupling. Recent progress on magnetic-field tunable RF/microwave devices are also covered, including novel non-reciprocal tunable bandpass filters with ultra wideband isolation, compact, low loss and high power handling phase shifters, etc. These novel tunable multiferroic heterostructures and devices and tunable magnetic devices provide great opportunities for next generation reconfigurable RF/microwave communication systems and radars, Spintronics, magnetic field sensing, etc.

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Pulsating fields of a thin film in a static magnetic field under vertical vibrations

Journal of Physics Conference Series ◽

10.1088/1742-6596/2103/1/012233 ◽

2021 ◽

Vol 2103 (1) ◽

pp. 012233

Author(s):

I V Volodin ◽

A A Alabuzhev

Keyword(s):

Magnetic Field ◽

Thin Film ◽

Surface Wave ◽

Film Thickness ◽

Static Magnetic Field ◽

Surface Profile ◽

Vertical Vibration ◽

Vibrational Amplitude ◽

Gravitational Forces ◽

Vertical Vibrations

Abstract In the present paper a dynamics of a thin ferrofluid film under the vertical vibration in a static magnetic field is examined. The vibrational amplitude is assumed to be greater than film thickness so that vibrational force is greater than magnetic and gravitational forces. The pulsating part and the averaged part of the hydrodynamics fields are obtained. The solution of pulsating part for the traveling surface wave is found. The equation for the averaged surface profile is found.

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On the Thermoelectric Power in Quantum Dots of Non-Parabolic Semiconductors in Thr Presence of a Classically Large Field

MRS Proceedings ◽

10.1557/proc-198-327 ◽

1990 ◽

Vol 198 ◽

Cited By ~ 5

Author(s):

Ktamkahya P. Ghatak ◽

B. De ◽

M. Mondal ◽

S.N. Biswas

Keyword(s):

Magnetic Field ◽

Quantum Dots ◽

Film Thickness ◽

Thermoelectric Power ◽

Experimental Observation ◽

Electron Concentration ◽

Large Field ◽

Large Magnetic Field ◽

Theoretical Results

ABSTRACTWe have studied the thermoelectric power in quantum dots (QDs) of non-parabolic semiconductors in the presence of a classically large magnetic field and we have taken A3N B2V, ternary chalcopyrite, II-VI and III-V semiconductors. It is found that the thermopower increases with increasing film thickness and decreasing electron concentration respectively in all the cases. The numerical values are greatest for Cd3As2 and least for InAs and the theoretical results are in ageement with the experimental observation as reported elsewhere.

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The Influence of Quantizing Magnetic Field on The Magnetic Susceptibilities in Ultra Thin Films of Dilute Magnetic Materials

MRS Proceedings ◽

10.1557/proc-313-375 ◽

1993 ◽

Vol 313 ◽

Cited By ~ 1

Author(s):

Kamakhya P Ghatak ◽

S. N. Biswas

Keyword(s):

Magnetic Field ◽

Experimental Data ◽

Thin Films ◽

Theoretical Analysis ◽

Film Thickness ◽

Magnetic Materials ◽

Ultrathin Films ◽

Surface Concentration ◽

Magnetic Susceptibilities ◽

Quantizing Magnetic Field

ABSTRACTIn this paper we have studied the dia and paramagnetic susceptibilities of the holes in ultrathin films of dilute magnetic materials in the presence of a quantizing magnetic field and compared the same with that of the bulk specimens under magnetic quantization for the purpose of relative comparison. It is found, taking Hg1−xMnxTe and Cd1−xMnxSe as examples, that both the susceptibilities increase with decreasing film thickness and increasing surface concentration in oscillatory Manners. The numerical values of the susceptibilities in ultrathin films of dilute magnetic materials are greater than that of the bulk and the theoretical analysis is in agreement with the experimental data as reported elsewhere.

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