A5008117868- Magnetic properties of thin films
- Physics of Superconductivity and Magnetism
- Rare-earth and actinide compounds
- Quantum and electron transport phenomena
- Magnetic Properties of Alloys
- Iron-based superconductors research
- Magnetic and transport properties of perovskites and related materials
- Magnetic Properties and Applications
- Theoretical and Computational Physics
- Heusler alloys: electronic and magnetic properties
- ZnO doping and properties
- Thermodynamic and Structural Properties of Metals and Alloys
- Intermetallics and Advanced Alloy Properties
- High-pressure geophysics and materials
- Molecular Junctions and Nanostructures
- Advanced Condensed Matter Physics
- Superconductivity in MgB2 and Alloys
- Semiconductor materials and interfaces
- Characterization and Applications of Magnetic Nanoparticles
- Nuclear Materials and Properties
- Superconducting Materials and Applications
- Quantum, superfluid, helium dynamics
- Crystal Structures and Properties
- Surface and Thin Film Phenomena
- Magneto-Optical Properties and Applications
Universidad Autónoma de Madrid
2015-2024
Bellingham Technical College
2015
University of Illinois Chicago
2014
KU Leuven
1995-2000
Oklahoma State University
2000
Lomonosov Moscow State University
1988-1997
Temper (United States)
1997
Azerbaijan Scientific-Research & Design-Prospecting Power Engineering Institute
1993-1994
Moscow State University
1987-1989
Azerbaijan National Academy of Sciences
1982
Magnonics addresses the physical properties of spin waves and utilizes them for data processing. Scalability down to atomic dimensions, operation in GHz-to-THz frequency range, utilization nonlinear nonreciprocal phenomena, compatibility with CMOS are just a few many advantages offered by magnons. Although magnonics is still primarily positioned academic domain, scientific technological challenges field being extensively investigated, proof-of-concept prototypes have already been realized...
Layered magnetic materials have been prepared using layer-by-layer deposition, a technique that allows engineering of the structure individual particles while remaining simple to carry out. Organic–inorganic sandwich films superparamagnetic Fe3O4 thus consisted densely packed assemblies nanocrystallites showed good adhesion variety substrates and excellent mechanical properties. Coating nanoparticles with shell SiO2 was found greatly reduce cooperative magnetization switching between...
Hybrid thin films are prepared from 8 to 10 nm Fe3O4 nanoparticles and exfoliated montmorillonite clay by using layer-by-layer assembly on poly(diallyldimethylammonium bromide), PDDA. Distinct stratification of the Fe3O4/PDDA/clay is obtained due sheetlike structure particles. This feature distinguishes these assemblies their polyelectrolyte−polyelectrolyte analogues, where layers individual polyelectrolytes strongly interdigitated. Being adsorbed PDDA strictly parallel substrate surface,...
We report on linear spin dynamics in the vortex state of Permalloy cylindrical dots subjected to an in-plane bias magnetic field. demonstrate experimentally by a broadband ferromagnetic resonance technique and simulations that breaking symmetry gradually changes suppresses azimuthal eigenmodes below nucleation field leads further appearance new eigenmodes. The parallel microwave pumping is shown be unique tool observe excitation modes localized near strongly shifted core for between...
Spin-orbit coupling (SOC) is a key interaction in spintronics, allowing electrical control of spin or magnetization and, vice versa, magnetic current. However, recent advances have revealed much broader implications SOC that also central to the design topological states with potential applications from low-energy dissipation and faster switching high tolerance disorder. resulting emergent interfacial spin-orbit fields are simply realized junctions through structural inversion asymmetry,...
Effective control of domain walls or magnetic textures in antiferromagnets promises to enable robust, fast, and nonvolatile memories. The lack net moment implies the need for creative ways achieve such a manipulation. We conducted study investigate changes force microscopy (MFM) imaging magnon-related mode Raman spectroscopy virgin NiO films under microwave pump. After MFM studies were conducted, combined action broadband (0.01–20 GHz, power scanned from −20 5 dBm) field (up 3 kOe) applied...
Broadband ferromagnetic resonance in square arrays of Permalloy circular dots with different interdot separations was measured the vortex ground state. The detected spin excitations show a complicated dependence their frequencies on coupling strength. A considerable influence separation gyrotropic frequency and splitting azimuthal wave detected. first doublet depend nonmonotonously spacing, whereas second this parameter is monotonous. observed effects are explained by both dipolar...
Abstract The response of superconducting devices to electromagnetic radiation is a core concept implemented in diverse applications, ranging from the currently used voltage standard single photon detectors astronomy. Suprisingly, sufficiently high power subgap may stimulate superconductivity itself. possibility stimulating type II superconductors, which interact also with vortex cores, remains however unclear. Here we report on enhanced by GHz Pb films presence vortices. stimulation effect...
The interaction between superconductivity and ferromagnetism in thin film superconductor/ferromagnet heterostructures is usually reflected by a change of the S layer set magnetic state F layers. Here we report converse effect: transformation magnetocrystalline anisotropy single Fe(001) layer, thus its preferred magnetization orientation, driven an underlying V through spin-orbit coupled MgO interface. We attribute this to additional contribution free energy ferromagnet arising from...
Fast and efficient switching of nanomagnets is one the main challenges in development future magnetic memories. We numerically investigate evolution static dynamic spin-wave (SW) magnetization short (50--400 nm length 120 diameter) cylindrical ferromagnetic nanowires, where competing configurations a single vortex (SV) Bloch-point domain wall (BP-DW) can be formed. For limited nanowire range (between 150 300 nm), we demonstrate reversible transitions induced by microwave field (forwards)...
Recent studies have revealed magnetically controllable thermoelectric effects in superconductor/ferromagnet (S/F) structures. A tunable cryogenic generator needs not only a high conversion factor between electricity and heat, but also large change the output when switching magnetic state of device. Here, we experimentally measure numerically model fully epitaxial F/S/F junctions based on commercially available, easily grown materials, as well their dependence configuration F electrodes. We...
We report the experimental observation of sub-Poissonian shot noise in single magnetic tunnel junctions, indicating importance tunneling via impurity levels inside barrier. For junctions with weak zero-bias anomaly conductance, Fano factor (normalized noise) depends on configuration being enhanced for antiparallel alignment ferromagnetic electrodes. propose a model sequential through nonmagnetic and paramagnetic barrier to qualitatively explain observations.
Low temperature (10K) high voltage bias dynamic conductivity (up to 2.7V) and shot noise 1V) were studied in epitaxial Fe(100)∕Fe–C∕MgO(100)∕Fe(100) magnetic tunnel junctions as a function of the state. The show large magnetoresistance (185% at 300K 330% 4K). Multiple sign inversion is observed for polarity when electrons scan electronic structure bottom Fe–C interface. shows Poissonian character. This demonstrates pure spin-dependent direct tunneling mechanism validates structural quality...
We investigate the magnetization dynamics in circular Permalloy dots with spatially separated magnetic vortices interconnected by domain walls (double vortex state). identify a novel type of quasi one-dimensional (1D) localized spin wave modes confined along walls, connecting each two cores edge half-antivortices. Variation mode eigenfrequencies dot sizes is quantitative agreement developed model, which considers dipolar origin 1D waves or so-called Winter's magnons [J. M. Winter, Phys. Rev....
Low dissipation data processing with spins is one of the promising directions for future information and communication technologies. Despite a signifcant progress, available magnonic devices are not broadband yet have restricted capabilities to redirect spin waves. Here we propose breakthrough approach wave manipulation in patterned magnetic nanostructures unmatched characteristics, which exploits waves analogous edge propagating along water-wall boundary. Using theory, micromagnetic...
The time dependent transient lateral photovoltaic effect has been studied with μs resolution and chopping frequencies in the kHz range, lithographically patterned 21 nm thick, 5, 10, 20 μm wide, 1500 long Co lines grown over naturally passivated p-type Si (100). We have observed a nearly linear dependence of transitorial response laser spot position. A sign change laser-off stage corroborated by numerical simulations. qualitative explanation suggests modification drift-diffusion model...
We report on room temperature 1∕f noise in fully epitaxial Fe (45nm)∕MgO (2.6nm)∕Fe (10nm) magnetic tunnel junctions (MTJs) with and without carbon doping of the Fe∕MgO bottom interface. have found that normalized (Hooge factor) asymmetry between parallel antiparallel states may strongly depend applied bias its polarity. Both types MTJs exhibit record low Hooge factors being at least one order magnitude smaller than previously reported.