The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform

M Vazquez - One of the best experts on this subject based on the ideXlab platform.

  • tunable asymmetric Magnetoimpedance effect in ferromagnetic nife cu co films
    Applied Physics Letters, 2014
    Co-Authors: Edson F Da Silva, M A Correa, M Gamino, A M H De Andrade, M Vazquez, F Bohn
    Abstract:

    We investigate the magnetization dynamics through the Magnetoimpedance effect in ferromagnetic NiFe/Cu/Co films. We observe that the Magnetoimpedance response is dependent on the thickness of the non-magnetic Cu spacer material. We verify asymmetric Magnetoimpedance in films with biphase magnetic behavior and explore the possibility of tuning the linear region of the Magnetoimpedance curves around zero magnetic field by varying the thickness of the spacer and probe current frequency. We discuss the experimental results in terms of the different mechanisms governing the magnetization dynamics at distinct frequency ranges, quasi-static magnetic properties, thickness of the spacer, and the kind of the magnetic interaction between the ferromagnetic layers. The results place films with biphase magnetic behavior exhibiting asymmetric Magnetoimpedance effect as very attractive candidates for application as probe element in the development of auto-biased linear magnetic field sensors.

  • tunable asymmetric Magnetoimpedance effect in ferromagnetic nife cu co films
    arXiv: Materials Science, 2014
    Co-Authors: Edson F Da Silva, M A Correa, M Gamino, A M H De Andrade, M Vazquez, F Bohn
    Abstract:

    We investigate the magnetization dynamics through the Magnetoimpedance effect in ferromagnetic NiFe/Cu/Co films. We observe that the Magnetoimpedance response is dependent on the thickness of the non-magnetic Cu spacer material, a fact associated to the kind of the magnetic interaction between the ferromagnetic layers. Thus, we present an experimental study on asymmetric Magnetoimpedance in ferromagnetic films with biphase magnetic behavior and explore the possibility of tuning the linear region of the Magnetoimpedance curves around zero magnetic field by varying the thickness of the non-magnetic spacer material, and probe current frequency. We discuss the experimental Magnetoimpedance results in terms of the different mechanisms governing the magnetization dynamics at distinct frequency ranges, quasi-static magnetic properties, thickness of the non-magnetic spacer material, and the kind of the magnetic interaction between the ferromagnetic layers. The results place ferromagnetic films with biphase magnetic behavior exhibiting asymmetric Magnetoimpedance effect as a very attractive candidate for application as probe element in the development of auto-biased linear magnetic field sensors.

  • nonlinear Magnetoimpedance and parametric excitation of standing spin waves in a glass covered microwire
    Applied Physics Letters, 2009
    Co-Authors: L Kraus, M Vazquez, G Infante, G A Badiniconfalonieri, J Torrejon
    Abstract:

    The giant Magnetoimpedance of an 8.5 μm glass-covered amorphous microwire was investigated in the frequency range of 10 MHz–3.5 GHz. It was found that when the exciting microwave current exceeds some threshold value, a periodic fine structure appears in the frequency dependence of the complex impedance. The appearance of this nonlinear phenomenon is interpreted to be a consequence of the parametric excitation of standing spin waves.

  • influences of annealing and wire geometry on the giant Magnetoimpedance effect in a glass coated microwire lc resonator
    Journal of Physics D, 2007
    Co-Authors: Manhhuong Phan, M Vazquez, C G Kim, Heebok Lee, Nguyen Quang Hoa
    Abstract:

    The influence of annealing and of wire geometry on the giant Magnetoimpedance (GMI) effect in a glass-coated microwire LC-resonator were systematically investigated. It was found that annealing magnetic microwires significantly varied the permeability and hence the GMI ratio, whereas the Magnetoimpedance response was sensitively altered with varying wire geometry of the LC-resonator. The magnitude of GMI is determined by the soft magnetic characteristics of the microwire and the effect of LC-resonance, while the multiple-peak GMI feature can be attributed to the LC-resonance circuit and the formation of standing magnetic waves within the sample. Interestingly, the GMI ratio reached the largest values of 400 000% and 270 000% at the resonance frequencies of 518.51 MHz and 146.32 MHz for Co83.2B3.3Si5.9Mn7.6 and Co67Fe3.8Ni1.4B11.5Si14.6Mo1.7 samples, respectively. The corresponding magnetic-field sensitivities of GMI are about 218 000%/Oe and 135 000%/Oe. These results are interesting for the development of a new family of ultra-sensitive and high-frequency magnetic sensors. The feature of a LC-resonance circuit can be used for improving the sensitivity of GMI-based magnetic sensors while selecting the working frequency.

  • giant Magnetoimpedance effect enhancement by circuit matching
    Sensors and Actuators A-physical, 2003
    Co-Authors: V Raposo, M Vazquez, A G Flores, M Zazo, J Iniguez
    Abstract:

    GMI response of amorphous wires can be greatly increased by working at resonant conditions in a LC cell. This feature of the circuit can be exploited to increase the sensibility of current GMI-based sensors while selecting the working frequency.

G V Kurlyandskaya - One of the best experts on this subject based on the ideXlab platform.

  • Magnetoimpedance biosensor prototype for ferrogel detection
    Journal of Magnetism and Magnetic Materials, 2017
    Co-Authors: E. Fernandez, G V Kurlyandskaya, A V Svalov, A P Safronov, F A Blyakhman, Burgoa A Beitia, I V Beketov
    Abstract:

    Abstract Ferrogels are composite materials widely introduced in the area of biomedical engineering as magnetic field sensitive transformers. These biomimetic materials can be prepared by incorporating monodomain magnetic nanoparticles into chemically crosslinked hydrogels. The properties of a biomimetic ferrogels taken for the study unlike that of the biological prototype might be set up by the synthesis and can be thoroughly controlled in a physical experiment. In this work we developed a giant Magnetoimpedance sensor with a multilayered FeNi/Ti-based sensitive element adapted for ferrogel studies. Ferrogels were synthesized by radical polymerization of acrylamide in a stable aqueous suspension of γ-Fe2O3 MNPs fabricated by laser target evaporation. The Magnetoimpedance measurements in initial state and in the presence of ferrogels with concentrations of nanoparticles from 0 to 2.4 wt% in a frequency range of 1–300 MHz allowed a precise characterization of the stray fields of the nanoparticles present in the ferrogel.

  • flexible thin film Magnetoimpedance sensors
    Journal of Magnetism and Magnetic Materials, 2016
    Co-Authors: E. Fernandez, A Garciaarribas, G V Kurlyandskaya, A V Svalov, Burgoa A Beitia, Aitor Larranaga
    Abstract:

    Abstract Magnetically soft thin film deposited onto polymer substrates is an attractive option for flexible electronics including Magnetoimpedance (MI) applications. MI FeNi/Ti based thin film sensitive elements were designed and prepared using the sputtering technique by deposition onto rigid and flexible substrates at different deposition rates. Their structure, magnetic properties and MI were comparatively analyzed. The main structural features were sufficiently accurately reproduced in the case of deposition onto cyclo olefine polymer substrates compared to glass substrates for the same conditions. Although for the best condition (28 nm/min rate) of the deposition onto polymer a significant reduction of the MI field sensitivity was found satisfactory for sensor applications sensitivity: 45%/Oe was obtained for a frequency of 60 MHz.

  • impedance and magnetic properties of cofecrsib amorphous ribbons near the curie point
    Technical Physics, 2013
    Co-Authors: A V Semirov, M S Derevyanko, Dmitry A Bukreev, A A Moiseev, G V Kurlyandskaya
    Abstract:

    The influence of temperature on the magnetic properties and Magnetoimpedance of Co64Fe3Cr3Si15B15 and Co67FCr3Si15B12 amorphous ribbons having different Curie points are studied. The impedance and its component are found to change greatly when the ribbons pass into the paramagnetic state. This finding can be used to determine the Curie point of ferromagnets and design high-sensitivity thermal transducers.

  • Magnetoimpedance of feni thin film meanders
    Solid State Phenomena, 2012
    Co-Authors: S. O. Volchkov, A A Yuvchenko, V N Lepalovskij, Eduardo Fernandez, G V Kurlyandskaya
    Abstract:

    The role of the geometrical parameters was studied for thin film based [FeNi (100 nm)/Cu (3 nm)]4/FeNi (100 nm)/Cu (500 nm)/[FeNi (100 nm)/Cu (3 nm)]4/FeNi (100 nm) Magnetoimpedance elements with open magnetic flux prepared by lithography technique. The maximum Magnetoimpedance sensitivity of 17 %/Oe was obtained for meander shaped sample, exceeding the value of the maximum sensitivity of 5 %/Oe of the single stripe sample. The highest values of the Magnetoimpedance were observed for relatively low frequency of order of 50 MHz convenient for technological applications. Both developed technology and obtained results can be useful for optimization of the design of miniaturized detectors of small magnetic field.

  • feni based Magnetoimpedance multilayers tailoring of the softness by magnetic spacers
    Applied Physics Letters, 2012
    Co-Authors: A V Svalov, E. Fernandez, A Garciaarribas, J Alonso, M L Fdezgubieda, G V Kurlyandskaya
    Abstract:

    The microstructure and magnetic properties of sputtered permalloy films and FeNi(170 nm)/X/FeNi(170 nm) (X = Co, Fe, Gd, Gd-Co) sandwiches were studied. Laminating of the thick FeNi film with various spacers was done in order to control the magnetic softness of FeNi-based multilayers. In contrast to the Co and Fe spacers, Gd and Gd-Co magnetic spacers improved the softness of the FeNi/X/FeNi sandwiches. The Magnetoimpedance responses were measured for [FeNi/Ti(6 nm)]2/FeNi and [FeNi/Gd(2 nm)]2/FeNi multilayers in a frequency range of 1–500 MHz: for all frequencies under consideration the highest Magnetoimpedance variation was observed for [FeNi/Gd(2 nm)]2/FeNi multilayers.

Mihail Ipatov - One of the best experts on this subject based on the ideXlab platform.

  • giant Magnetoimpedance in rapidly quenched materials
    Journal of Alloys and Compounds, 2020
    Co-Authors: Mihail Ipatov, J.m. Blanco, J. Gonzalez, M. Churyukanova, A. Zhukov, P Corteleon, Gonzalez L Legarreta, S. Taskaev
    Abstract:

    Abstract We present an overview of the factors as well as post processing tools allowing optimization of magnetic softness and GMI effect of rapidly quenched materials: microwires and ribbons. Generally, low coercivity and high GMI effect have been observed in as-prepared Co-rich compositions. Annealing at adequate conditions can be very effective for manipulation of the magnetic properties and GMI effect of amorphous and nanocrystalline rapidly quenched materials. After annealing of Co-rich compositions, we can observe transformation of inclined hysteresis loops to rectangular. However, at certain annealing conditions GMI effect can be improved. Using stress-annealing, GMI effect of both Fe-rich and Co-rich microwires as well as of amorphous ribbons can be improved. On the other hand, in Fe-rich FeCuNbSiB microwires after appropriate annealing we observed considerable magnetic softening and GMI effect enhancement. The other promising post-processing allowing GMI effect optimization is Joule heating.

  • Giant Magnetoimpedance Microwires for Sensor Applications
    AES20, 2020
    Co-Authors: Arkady Zhukov, P. Corte-león, Juan Maria Blanco, Mihail Ipatov, Lorena González-legarreta, Valentina Zhukova
    Abstract:

    The influence of post-processing (annealing and stress-annealing) on the Giant Magnetoimpedance (GMI) effect in thin magnetic microwires is reviewed. High GMI effect has been observed in Co-rich magnetic microwires with vanishing magnetostriction coefficient. Post-processing including annealing or stress-annealing at adequate conditions allows further improvement of GMI effect in Co-rich magnetic microwires

  • Engineering of Giant Magnetoimpedance Effect in Co-rich Microwires by Joule heating
    2018 International Conference on Electromagnetics in Advanced Applications (ICEAA), 2018
    Co-Authors: Arcady Zhukov, P. Corte-león, Juan Maria Blanco, Julian Gonzlez, Mihail Ipatov, Valentina Zhukova
    Abstract:

    Joule heating of the Co-rich glass-coated microwire allows remakrable improvement of magnetic softness and giant Magnetoimpedance effect. At optimal joule heating conditions we observed GMI ratio up to 650%, low magnetic anisotropy field of about 25 A/m and coercivity of about 2 A/m. Observed experimental dependencies are discussed considering various factors affecting the magnetic properties of studied microwire upon Joule heating: induced magnetic anisotropy, internal stresses relaxation and radial distribution of magnetic anisotropy.

  • Optimization of GMI Effect and Magnetic Properties of Co-Rich Microwires by Joule Heating
    2018 Progress in Electromagnetics Research Symposium (PIERS-Toyama), 2018
    Co-Authors: Arcady Zhukov, P. Corte-león, Mihail Ipatov, Valentina Zhukova
    Abstract:

    Joule heating of the Co-rich glass-coated microwire allows remarkable improvement of magnetic softness and giant Magnetoimpedance effect. At optimal Joule heating conditions we observed GMI ratio up to 650%, low magnetic anisotropy field of about 25 A/m and coercivity of about 2 A/m. Observed experimental dependencies are discussed considering various factors affecting the magnetic properties of studied microwire upon Joule heating: induced magnetic anisotropy, internal stresses relaxation and radial distribution of magnetic anisotropy.

  • Tailoring of magnetic softness and GMI effect in Fe-rich thin magnetic wires
    AIP Publishing LLC, 2018
    Co-Authors: Valentina Zhukova, P. Corte-león, Mihail Ipatov, J.m. Blanco, A. Talaat, J. Olivera, J. Gonzalez, Arkady Zhukov
    Abstract:

    We present comparative studies of magnetic properties and giant Magnetoimpedance (GMI) effect of Fe and Co-rich microwires. As-prepared Co-rich microwires present much higher GMI ratio. The impact of the stress-annealing on magnetic softness and Magnetoimpedance effect of Fe-rich microwires has been studied. The large improvement of the Magnetoimpedance response by the stress-annealing is observed. We have achieved GMI ratio increase by an order of magnitude after stress-annealing of Fe-rich microwire. Observed stress-induced anisotropy and related changes of magnetic properties are discussed considering internal stresses relaxation and “back-stresses”

A. Zhukov - One of the best experts on this subject based on the ideXlab platform.

  • giant Magnetoimpedance in rapidly quenched materials
    Journal of Alloys and Compounds, 2020
    Co-Authors: Mihail Ipatov, J.m. Blanco, J. Gonzalez, M. Churyukanova, A. Zhukov, P Corteleon, Gonzalez L Legarreta, S. Taskaev
    Abstract:

    Abstract We present an overview of the factors as well as post processing tools allowing optimization of magnetic softness and GMI effect of rapidly quenched materials: microwires and ribbons. Generally, low coercivity and high GMI effect have been observed in as-prepared Co-rich compositions. Annealing at adequate conditions can be very effective for manipulation of the magnetic properties and GMI effect of amorphous and nanocrystalline rapidly quenched materials. After annealing of Co-rich compositions, we can observe transformation of inclined hysteresis loops to rectangular. However, at certain annealing conditions GMI effect can be improved. Using stress-annealing, GMI effect of both Fe-rich and Co-rich microwires as well as of amorphous ribbons can be improved. On the other hand, in Fe-rich FeCuNbSiB microwires after appropriate annealing we observed considerable magnetic softening and GMI effect enhancement. The other promising post-processing allowing GMI effect optimization is Joule heating.

  • Tailoring of Magnetoimpedance effect and magnetic softness of Fe-rich glass-coated microwires by stress- annealing
    Nature Publishing Group, 2018
    Co-Authors: V Zhukova, Mihail Ipatov, J.m. Blanco, M. Churyukanova, S. Taskaev, A. Zhukov
    Abstract:

    Abstract There is a pressing need for improving of the high-frequency magneto-impedance effect of cost-effective soft magnetic materials for use in high-performance sensing devices. The impact of the stress-annealing on magnetic properties and high frequency impedance of Fe-rich glass-coated microwires was studied. Hysteresis loops of Fe-rich microwires have been considerably affected by stress- annealing. In stress-annealed Fe- rich microwire we obtained drastic decreasing of coercivity and change of character of hysteresis loop from rectangular to linear. By controlling stress-annealing conditions (temperature and time) we achieved drastic increasing (by order of magnitude) of giant Magnetoimpedance ratio. Coercivity, remanent magnetization, diagonal and of-diagonal Magnetoimpedance effect of Fe-rich microwires can be tuned by stress-annealing conditions: annealing temperature and time. Observed experimental results are discussed considering relaxation of internal stresses, compressive “back-stresses” arising after stress annealing and topological short range ordering

  • estimation of the frequency and magnetic field dependence of the skin depth in co rich magnetic microwires from gmi experiments
    Journal of Science: Advanced Materials and Devices, 2016
    Co-Authors: Mihail Ipatov, A. Talaat, A B Granovsky, A. Zhukov, V Zhukova
    Abstract:

    Abstract We studied giant Magnetoimpedance (GMI) effect in magnetically soft amorphous Co-rich microwires in the extended frequency range. From obtained experimentally dependences of the GMI ratio on magnetic field at different frequencies we estimated the penetration depth and its dependence on applied magnetic field and frequency.

  • Magnetoimpedance sensitive to dc bias current in amorphous microwires
    Applied Physics Letters, 2010
    Co-Authors: Mihail Ipatov, V Zhukova, A. Zhukov, J. Gonzalez
    Abstract:

    We have investigated the impedance dependence of magnetically soft microwire on the internal circumferential magnetic field HB created by the dc bias current IB and theoretically and experimentally demonstrated that in a conductor with helical magnetic anisotropy, the high frequency impedance depends on the dc bias current IB (or the corresponding bias field HB) and this dependence is hysteretic. We have experimentally observed a change of impedance more than 35% upon changing the bias current. The possible applications of the dc current-driven Magnetoimpedance effect are discussed.

  • studies of magnetic properties and giant Magnetoimpedance effect in ultrathin magnetically soft amorphous microwires
    Journal of Applied Physics, 2008
    Co-Authors: V Zhukova, Mihail Ipatov, J.m. Blanco, J. Gonzalez, A. Zhukov
    Abstract:

    We report novel results on studies of giant Magnetoimpedance (GMI) effect and magnetic properties in ultrathin amorphous glass-coated microwires with nearly zero and negative magnetostriction constant and metallic nucleus diameter ranging within 6 and 12μm. Off-diagonal MI curve of Co67.1Fe3.8Ni1.4Si14.5B11.5Mo1.7 microwire exhibits asymmetrical shape with almost linear growth within the field range from −Hm to Hm associated with the anisotropy field. Co74B13Si11C2 microwire possesses hysteretic off-diagonal MI curve. Current annealing significantly changes off-diagonal MI curves, especially in the case of Co74B13Si11C2 microwire.

Valentina Zhukova - One of the best experts on this subject based on the ideXlab platform.