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Magnetotransport properties of CrO₂ nanowires fabricated by selective area growth

Prateek, K. (author), Bolhuis, M. (author), Ben Hamida, A. (author), Scholma, D. (author), Conesa Boj, S. (author), Aarts, Jan (author)

Chromium dioxide (CrO₂) nanowires with their half-metallic ferromagnetic properties have shown great promise in spintronics applications. However, growth of such wires remains challenging. We used the Selective Area growth method to fabricate high quality epitaxial CrO₂ wires on a TiO₂ substrate, using...

journal article 2023

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Magnetic domain structure and magneto-transport properties of laser ablated Co₄₀Fe₄₀B₂₀ thin films

Swamy, G. Venkat (author), Rout, P.K. (author), Pandey, Himanshu (author), Riscob, B. (author), Basheed, G. A. (author)

We report the magnetic domain structure, and electrical and magnetoresistance properties of laser ablated Co₄₀Fe₄₀B₂₀ (CoFeB) (6 to 36 nm) thin films deposited on SiO₂ / Si(001) substrates. Magnetic force microscopy performed on annealed CoFeB thin films revealed larger magnetic domains, which are...

journal article 2023

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Quantum simulation using arrays of gate-defined quantum dots

Mukhopadhyay, U. (author)

We are entering the era of the second quantum revolution, where we aim to harness the power of quantum mechanics to create new technologies. Quantum technologies have the potential to revolutionize the fields of simulation, computation, communication, sensing, metrology, and many others. Here we discuss analog quantum simulation, which has...

doctoral thesis 2019

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Effect of stress-induced magnetization on crack monitoring by self magnetic flux leakage method

van der Horst, Menno (author), van Kreveld, Sylvia (author), Kaminski, M.L. (author)

Wireless crack monitoring on ships and offshore structures based on Self Magnetic Flux Leakage (SMFL) measurements is a promising method to guarantee the structural integrity in a more effective way, leading to reduced operational costs and increased safety. For accurate crack sizing, the SMFL measurements must be interpreted correctly, also...

journal article 2019

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Magnetically assisted bilayer composites for soft bending actuators

Jang, S.H. (author), Na, Seon Hong (author), Park, Yong Lae (author)

This article presents a soft pneumatic bending actuator using a magnetically assisted bilayer composite composed of silicone polymer and ferromagnetic particles. Bilayer composites were fabricated by mixing ferromagnetic particles to a prepolymer state of silicone in a mold and asymmetrically distributed them by applying a strong non-uniform...

journal article 2017

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Testing and Numerical Simulation of Magnetic Fields Affected by Presence of Fatigue Cracks

van der Horst, M.P. (author)

conference paper 2014

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Tuning the metamagnetic transition in the (Co, Fe)MnP system for magnetocaloric purposes

Guillou, F. (author), Brück, E. (author)

The inverse magnetocaloric effect taking place at the antiferro-to-ferromagnetic transition of (Co,Fe)MnP phosphides has been characterised by magnetic and direct ?Tad measurements. In Co0.53Fe0.47MnP, entropy change of 1.5?Jkg?1?K?1 and adiabatic temperature change of 0.6?K are found at room temperature for an intermediate field change (?B?=?1...

journal article 2013

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Exchange magnetic field torques in YIG/Pt bilayers observed by the spin-Hall magnetoresistance

Vlietstra, N. (author), Shan, J. (author), Castel, V. (author), Youssef, J.B. (author), Bauer, G.E.W. (author), Van Wees, B.J. (author)

The effective field torque of an yttrium-iron-garnet (YIG) film on the spin accumulation in an attached platinum (Pt) film is measured by the spin-Hall magnetoresistance (SMR). As a result, the magnetization direction of a ferromagnetic insulating layer can be measured electrically. Experimental transverse and longitudinal resistances are well...

journal article 2013

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Evidence of the Griffiths phase in multiferroic BiMnO3 and BiFe0.5Mn0.5O3 films

Prokhorov, V.G. (author), Kaminsky, G.G. (author), Kim, J.M. (author), Yoo, Y.J. (author), Lee, Y.P. (author), Svetchnikov, V.L. (author), Levchenko, G.G. (author), Nikolaenko, Y.M. (author), Khokhlov, V.A. (author)

Microstructure and magnetic properties of BiMnO3 and BiFe0.5Mn0.5O3 films, prepared by rf magnetron sputtering on LaAlO3 (001) single-crystalline substrate, are investigated. The selected-area electron diffraction analysis allows us to identify the crystal structure of the BiMnO3 film as orthorhombic, while the BiFe0.5Mn0.5O3 film has a...

journal article 2012

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Thermal spin pumping and magnon-phonon-mediated spin-Seebeck effect

Uchida, K. (author), Ota, T. (author), Adachi, H. (author), Xiao, J. (author), Nonaka, T. (author), Kajiwara, Y. (author), Bauer, G.E.W. (author), Maekawa, S. (author), Saitoh, E. (author)

The spin-Seebeck effect (SSE) in ferromagnetic metals and insulators has been investigated systematically by means of the inverse spin-Hall effect (ISHE) in paramagnetic metals. The SSE generates a spin voltage as a result of a temperature gradient in a ferromagnet, which injects a spin current into an attached paramagnetic metal. In the...

journal article 2012

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Defect evolution during annealing of deformed FeSi alloys studied by positron annihilation spectroscopy

Mostafa, K.M. (author), González Cámara, F. (author), Petrov, R. (author), Rodriguez Calvillo, P. (author), De Grave, E. (author), Segers, D. (author), Houbaert, Y. (author)

High silicon steel is widely used in electrical appliances. Alloying iron with silicon improves its magnetic performance. A silicon content up to 6.5 wt. % gives excellent magnetic properties such as high saturation magnetization, near zero magnetostriction and low iron loss in high frequencies. Their workability is greatly reduced by the...

journal article 2011

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Evidence of non-Dzyaloshinskii–Moriya ferromagnetism in epitaxial BiFeO3 films

Prokhorov, V.G. (author), Kaminsky, G.G. (author), Kim, J.M. (author), Eom, T.W. (author), Park, J.S. (author), Lee, Y.P. (author), Svetchnikov, V.L. (author), Levtchenko, G.G. (author), Nikolaenko, Y.M. (author), Khokhlov, V.A. (author)

X-ray diffraction analysis and high-resolution electron microscopy of BiFeO3 films prepared by dc magnetron sputtering on single-crystal LaAlO3 (001) substrates reveal that the films have a highly c-oriented orthorhombic crystalline structure. The magnetic properties of the BiFeO3 films are typical of ensembles of interacting superparamagnetic...

journal article 2011

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Feedback control of noise in spin valves by the spin-transfer torque

Bandopadyay, S. (author), Brataas, A. (author), Bauer, G.E.W. (author)

The miniaturization of magnetic read heads and random access memory elements makes them vulnerable to thermal fluctuations. We demonstrate how current-induced spin-transfer torques can be used to suppress the effects of thermal fluctuations. This enhances the fidelity of perpendicular magnetic spin valves. The simplest realization is a dc to...

journal article 2011

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From single- to double-first-order magnetic phase transition in magnetocaloric Mn1−xCrxCoGe compounds

Trung, N.T. (author), Biharie, V. (author), Zhang, L. (author), Caron, L. (author), Buschow, K.H.J. (author), Brück, E.H. (author)

Substitution of some Cr for Mn atoms in MnCoGe was employed to control the magnetic and structural transitions in this alloy to coincide, leading to a single first-order magnetostructural transition from the ferromagnetic to the paramagnetic state with a giant magnetocaloric effect observed near room temperature. Further increase in the Cr...

journal article 2010

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Barnett effect in thin magnetic films and nanostructures

Bretzel, S. (author), Bauer, G.E.W. (author), Tserkovnyak, Y. (author), Brataas, A. (author)

The Barnett effect refers to the magnetization induced by rotation of a demagnetized ferromagnet. We describe the location and stability of stationary states in rotating nanostructures using the Landau–Lifshitz–Gilbert equation. The conditions for an experimental observation of the Barnett effect in different materials and sample geometries are...

journal article 2009

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Tunable thermal hysteresis in MnFe(P,Ge) compounds

Trung, N.T. (author), Ou, Z.Q. (author), Gortenmulder, T.J. (author), Tegus, O. (author), Buschow, K.H.J. (author), Brück, E. (author)

Structural, magnetic, and magnetocaloric properties of the MnFe(P,Ge) compounds were systematically studied on both bulk alloys and melt-spun ribbons. The experimental results show that the critical behavior of the phase transition can be controlled by changing either the compositions or the annealing conditions. The thermal hysteresis is found...

journal article 2009

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Microstructures and the corresponding magnetic properties of half-doped Nd0.5Sr0.5MnO3 films

Prokhorov, V.G. (author), Hyun, Y.H. (author), Park, J.S. (author), Kim, J.B. (author), Kim, G.H. (author), Lee, Y.S. (author), Lee, Y.P. (author), Svetchnikov, V.L. (author)

The microstructural and magnetic properties of amorphous, nanoclustered, and self-organized bilayer Nd0.5Sr0.5MnO3 films, prepared by rf magnetron sputtering, are investigated. The amorphous film was found to be a typical paramagnet with free motion of the individual Mn spins, and the magnetic properties are well described on the basis of the...

journal article 2008

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Magnetic materials and devices for integrated radio-frequency electronics

Khalili Amiri, P. (author)

doctoral thesis 2008

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Current-induced noise and damping in nonuniform ferromagnets

Foros, J. (author), Brataas, A. (author), Tserkovnyak, Y. (author), Bauer, G.E.W. (author)

In the presence of spatial variation in the magnetization direction, electric current noise causes a fluctuating spin-transfer torque that increases the fluctuations of the ferromagnetic order parameter. By the fluctuationdissipation theorem, the fluctuations at thermal equilibrium are related to the viscous magnetization damping, which in...

journal article 2008

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Spin-transfer torque in magnetic tunnel junctions: Scattering theory

Xiao, J. (author), Bauer, G.E.W. (author), Brataas, A. (author)

We study the bias-dependent spin-transfer torque in magnetic tunnel junctions in the Stoner model by scattering theory. We show that the in-plane (Slonczewski type) torque vanishes and subsequently reverses its direction when the bias voltage becomes larger or the barrier wider than material and device-dependent critical values. We are able to...

journal article 2008