A5036447133- Magnetic properties of thin films
- Plasmonic and Surface Plasmon Research
- Magnetic Properties and Applications
- Gold and Silver Nanoparticles Synthesis and Applications
- Magneto-Optical Properties and Applications
- Photonic and Optical Devices
- Theoretical and Computational Physics
- ZnO doping and properties
- Surface and Thin Film Phenomena
- Photonic Crystals and Applications
- Physics of Superconductivity and Magnetism
- Optical Coatings and Gratings
- Advanced Fiber Optic Sensors
- Metamaterials and Metasurfaces Applications
- Copper Interconnects and Reliability
- Magnetic Properties of Alloys
- nanoparticles nucleation surface interactions
- Semiconductor materials and devices
- Electron and X-Ray Spectroscopy Techniques
- Surface Roughness and Optical Measurements
- Metallurgical and Alloy Processes
- Advanced Chemical Physics Studies
- Advanced Materials Characterization Techniques
- Metallic Glasses and Amorphous Alloys
- Nonlinear Optical Materials Studies
Institute of Micro and Nanotechnology
2007-2023
Universidad Autónoma de Madrid
1989-2023
Centro Nacional de Microelectrónica
2007-2016
Consejo Superior de Investigaciones Científicas
2004-2014
Unidades Centrales Científico-Técnicas
2012
JDSU (United States)
2011
University of Michigan
2007-2009
National Research Council
2009
Emerald Coast Science Center
2007
IBM Research - Almaden
1993-2002
Nanosystems with combined magnetic and plasmonic functionalities have in recent years become an active topic of research. By adequate internal architecture the constituting components, magneto‐optical activity these systems can be greatly increased due to electromagnetic field enhancement associated plasmon resonance. Simultaneously, functionality permits control properties by external field, which allows development devices. These materials find applications in, for example, gas biosensing...
A chemical-ordering-induced peak in the polar magneto-optical Kerr effect spectra of FePt compounds is found to be quantitative agreement with predictions based on ab initio calculations. Experimental epitaxial molecular-beam-epitaxy grown FePt(001) films reveal a more than twofold enhancement rotation if full chemical ordering present. spectral feature at 2-eV photon energy shows up \ensuremath{\sim}0.8\ifmmode^\circ\else\textdegree\fi{}, which strongly correlated presence perpendicular...
Growth of epitaxial films the L10 phase FePt, with tetragonal c axis along either film normal or in-plane, is described. Films were grown by coevaporation Fe and Pt, under ultrahigh vacuum conditions, onto a seed Pt on MgO SrTiO3 substrates. The perpendicular in-plane orientation was controlled selecting (001) (110) substrate plane, respectively. Nearly complete chemical ordering achieved for growth at 500 °C both orientations. Magnetic magneto-optical characterization these confirmed huge...
We present tunneling experiments on Fe(001)/MgO(20 Å)/FeCo(001) single-crystal epitaxial junctions of high quality grown by sputtering and laser ablation. Tunnel magnetoresistance measurements give 60% at 30 K, to be compared with 13% obtained recently (001)-oriented Fe/amorphous-Al2O3/FeCo tunnel junctions. This difference demonstrates that the spin polarization electrons is not directly related density states free metal surface—Fe(001) in this case—but depends actual electronic structure...
A nanostructure composed of Au/Co/Au nanodisks is fabricated. The behaviour this system completely different to that a continuous layer. There relative enhancement the Kerr rotation and ellipticity, as well strong dependence on particle size. origin these properties plasmonlike structure supported by nanosandwiches.
We demonstrate magnetic field control of surface plasmon excitations in noble-metal/ferromagnetic/noble metal trilayers, analogous to the effects previously observed semiconductor structures. show that coupling an external plasmon-polariton wave vector is greatly enhanced metallic structure due ferromagnetic nature one its constituents. The could be used modulate response ultrasensitive spectroscopic applications.
Anisotropy of the energy dependent polar magneto-optical Kerr effect as a function angle between magnetization and crystallographic axes is reported. The results are obtained on epitaxially oriented opaque films hcp Co grown in two different orientations by molecular beam epitaxy. Respective spectra fcc found to be insensitive direction. This anisotropy correlated with presence strong magnetocrystalline phase Co. A perturbation theory treatment spin orbit coupline correctly predicts order...
Cobalt-copper single-crystal superlattices were grown by epitaxy on a Cu(100) substrate with different bilayer thicknesses between 20 and 30 A\r{}. Polarized unpolarized neutron-diffraction characterization shows good structural quality antiferromagnetic ordering of the at zero field magnetic moments in film plane. Magnetization measurements are consistent neutron data, showing moment very close to saturation value bulk cobalt (1.7${\ensuremath{\mu}}_{B}$) as well complex dependence applied field.
The structural and magnetic properties of 1000-Å-thick epitaxial FexPt1−x(001) alloy films, grown by molecular beam epitaxy with x≂0.5, have been studied as a function growth temperature. X-ray diffraction analysis showed that the long-range order parameter increased from near zero for films at 100 °C to maximum 0.93 in 500 °C. Over this range easy axis changed in-plane perpendicular polar Kerr rotation strongly. Spontaneous ordering these has an activation energy ∼0.2 eV, consistent barrier...
Metal-dielectric Au-Co-SiO2 magnetoplasmonic nanodisks are found to exhibit large magneto-optical activity and low optical losses. The internal architecture of the is such that, in resonant conditions, electromagnetic field undertakes a particular spatial distribution. This makes it possible maximize at magneto-optically active layers minimize other, optically lossy ones. Combining materials with ferromagnetic plasmonic properties has recently become an area research.1-12 generation...
In this paper, we analyze the magnetoplasmonic (MP) features and sensing capabilities of Au/Fe/Au trilayer structures, as transducers magneto-optic surface plasmon resonance (MOSPR) biosensor. This biosensor, which can surpass sensitivity standard SPR sensor, is based on a MP modulation technique generated by simultaneous stimulation polaritons (SPP) transversal magneto-optical Kerr effect (TMOKE). We study activity trilayers function thickness position Fe layer. first demonstrate that kind...
Surface plasmon polariton (SPP) excitation effects on the magneto-optical (MO) activity of Au capped Ag/Co/Ag trilayers are studied as a function Co thickness. An enhancement transverse MO Kerr signal under SPP compared with that obtained without is measured maximum value 150 times for trilayer 8 nm Co. Such due to also five higher than in Au/Co/Au similar conditions. The lower optical absorption range and sharper resonance Ag vs responsible these values. On other hand, magnetic...
Porous TiO2 thin films deposited by glancing angle deposition are used as sensing layers to monitor their capabilities towards Volatile Organic Compounds both in a standard Surface Plasmon Resonance (SPR) sensor and Magneto-Optical (MO-SPR) configuration order compare performances. Here our results on the enhanced capability of these functionalized MO-SPR sensors with Au/Co/Au transducers respect traditional SPR gas presented.
We study how the magneto-optical activity in polar configuration of continuous Au/Co/Au trilayers is affected by excitation localized plasmon resonances an array Au nanodiscs fabricated on top them over a dielectric SiO 2 spacer.We show that effect twofold.First, it optimizes absorption light at specific photon energies corresponding to surface array, modifying reflectivity system (we define this as purely optical contribution).Second, upon resonance excitation, electromagnetic field whole...
The deposition of a dielectric overlayer on top Au/Co/Au multilayer films can significantly enhance the magnetic field induced modulation surface plasmon polariton (SPP) wave vector. This enhancement is analyzed as function thickness and associated SPP electromagnetic confinement redistribution. decrease in propagation distance taken into account by analyzing an adequate figure merit.
Epitaxial thin films of cobalt ranging from 1 ML up to 10 have been grown on a Cu(100) substrate and characterized by LEED. The is found grow, adopting slight tetragonal distortion its high-temperature FCC phase. Further growth 5 Cu top Co film results in an almost perfect surface.
An ultrafast time-resolved magneto-optical pump probe is applied to study spin-relaxation processes in a ferromagnetic ${\mathrm{CoPt}}_{3}$ alloy film. Following spin-selective photoexcitation with circularly polarized femtosecond pulses, transient Kerr ellipticity tracks the evolution of nonequilibrium spin system. We isolate two distinct processes: subpicosecond component due relaxation coherently electrons, and slower (\ensuremath{\sim}10 psec) associated thermalized distribution...
We show that the tilt angle of nanostructures obtained by glancing sputtering is finely tuned selecting adequate argon pressure. At low pressures, a ballistic deposition regime dominates, yielding high directional atoms form tilted nanocolumns. High pressures lead to diffusive which gives rise vertical columnar growth. Monte Carlo simulations reproduce experimental results indicating loss directionality sputtered particles in gas phase, together with self-shadowing mechanism at surface, are...
We show that the interaction between a plasmonic and magnetoplasmonic metallic nanodisk leads to appearance of magneto-optical activity in purely disk induced by one. Moreover, at specific wavelengths cancels net electromagnetic field component, strongly reducing whole system. The MO has characteristic Fano spectral shape, resulting inhibition constitutes counterpart transparency.