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Félix Vidal - One of the best experts on this subject based on the ideXlab platform.
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angular dependence of the fluctuation Magnetization Vector above the superconducting transition of a highly anisotropic high tc cuprate
arXiv: Superconductivity, 2013Co-Authors: R. I. Rey, N. Cotón, J. D. Dancausa, J. M. Doval, A. Wahl, M. Tello, J Mosqueira, A Ramosalvarez, Félix VidalAbstract:In highly anisotropic cuprate superconductors it is generally accepted that the reversible Magnetization Vector, M, is essentially perpendicular to the superconducting CuO2 layers in a wide range of crystal orientations with respect to the applied magnetic field, H. In a recent work [J. Mosqueira et al., Phys. Rev. B 84, 134504 (2011)] it is shown, however, that the dependence of M on the H orientation in the reversible mixed state of a high-quality Tl-based cuprate presents a notable deviation from this behavior. Here we extend these measurements to the fluctuation region above Tc, in order to check whether the above mentioned effect is also present.
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Angular Dependence of the Fluctuation Magnetization Vector Above the Superconducting Transition of a Highly Anisotropic High-Tc Cuprate
Journal of Superconductivity and Novel Magnetism, 2012Co-Authors: R. I. Rey, Jesús Mosqueira, N. Cotón, J. D. Dancausa, J. M. Doval, A. Ramos-Álvarez, A. Wahl, M. Tello, Félix VidalAbstract:In highly anisotropic cuprate superconductors it is generally accepted that the reversible Magnetization Vector, \(\vec{M}\), is essentially perpendicular to the superconducting CuO2 layers in a wide range of crystal orientations with respect to the applied magnetic field, \(\vec{H}\). In a recent work (Mosqueira et al. in Phys. Rev. B 84:134504, 2011) it is shown, however, that the dependence of \(\vec{M}\) on the \(\vec{H}\) orientation in the reversible mixed state of a high-quality Tl-based cuprate presents a notable deviation from this behavior. Here we extend these measurements to the fluctuation region above Tc, in order to check whether the above-mentioned effect is also present.
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Angular slippage from the crystallographic c axis of the reversible Magnetization Vector in a tilted crystal of a highly anisotropic cuprate superconductor
Physical Review B, 2011Co-Authors: Jesús Mosqueira, R. I. Rey, A. Wahl, Félix VidalAbstract:The Magnetization Vector \vec M was measured in the reversible region of the mixed state of a high quality Tl2Ba2Ca2Cu3O10 single crystal as a function of temperature and for different magnetic field amplitudes and orientations. These measurements allowed to study the \vec M components perpendicular and parallel to the CuO2 layers (Mperp and Mpara, respectively) under arbitrary values for the corresponding components of the applied magnetic field, Hperp and Hpara. For temperatures close to Tc (in the critical fluctuation region) we observed Mperp(Hperp,Hpara) Mperp(Hperp,0) and Mpara(Hperp,Hpara)~0, as expected for an extremely anisotropic material. However, deviations from this behavior are observed at lower temperatures in the London region. In particular, the Mperp amplitude under a constant Hperp decreases on increasing Hpara. In turn, in spite of the experimental uncertainties affecting Mpara (mainly associated with the rotating sample holder), its amplitude under a constant Hpara becomes observable on increasing Hperp. Both effects lead to an angular slippage of the Magnetization Vector \vec M from the c crystallographic axis when the applied magnetic field is tilted from that axis. The Mperp behavior is phenomenologically explained in the framework of Lawrence-Doniach approaches for single layered superconductors by just assuming a slight angular dependence of the so-called vortex structure constant. However, the observed Mpara is orders of magnitude larger than expected, a fact which is related to the multilayered nature of the compound studied. Our present results also directly affect the interpretation of recent measurements of the magnetic torque in other extremely anisotropic high-Tc cuprates.
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Magnetization Vector in the reversible region of the highly anisotropic cuprate superconductor Tl2Ba2Ca2Cu3O10: Anisotropy factor and the role of two-dimensional vortex fluctuations
Physical Review B, 2010Co-Authors: Jesús Mosqueira, R. I. Rey, Félix VidalAbstract:By using a high quality Tl2Ba2Ca2Cu3O10 (Tl-2223) single crystal as an example, the Magnetization Vector was probed in the reversible region of highly anisotropic cuprate superconductors. For that, we have measured its components along and transverse to the applied magnetic field for different crystal orientations. The analysis shows that the angular dependence of the perpendicular component of the Magnetization Vector follows the one predicted by a London-like approach which includes a contribution associated with the thermal fluctuations of the 2D vortex positions. For the Tl-2223 crystal studied here, a lower bound for the anisotropy factor was estimated to be about 190.
Jesús Mosqueira - One of the best experts on this subject based on the ideXlab platform.
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Angular Dependence of the Fluctuation Magnetization Vector Above the Superconducting Transition of a Highly Anisotropic High-Tc Cuprate
Journal of Superconductivity and Novel Magnetism, 2012Co-Authors: R. I. Rey, Jesús Mosqueira, N. Cotón, J. D. Dancausa, J. M. Doval, A. Ramos-Álvarez, A. Wahl, M. Tello, Félix VidalAbstract:In highly anisotropic cuprate superconductors it is generally accepted that the reversible Magnetization Vector, \(\vec{M}\), is essentially perpendicular to the superconducting CuO2 layers in a wide range of crystal orientations with respect to the applied magnetic field, \(\vec{H}\). In a recent work (Mosqueira et al. in Phys. Rev. B 84:134504, 2011) it is shown, however, that the dependence of \(\vec{M}\) on the \(\vec{H}\) orientation in the reversible mixed state of a high-quality Tl-based cuprate presents a notable deviation from this behavior. Here we extend these measurements to the fluctuation region above Tc, in order to check whether the above-mentioned effect is also present.
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Angular slippage from the crystallographic c axis of the reversible Magnetization Vector in a tilted crystal of a highly anisotropic cuprate superconductor
Physical Review B, 2011Co-Authors: Jesús Mosqueira, R. I. Rey, A. Wahl, Félix VidalAbstract:The Magnetization Vector \vec M was measured in the reversible region of the mixed state of a high quality Tl2Ba2Ca2Cu3O10 single crystal as a function of temperature and for different magnetic field amplitudes and orientations. These measurements allowed to study the \vec M components perpendicular and parallel to the CuO2 layers (Mperp and Mpara, respectively) under arbitrary values for the corresponding components of the applied magnetic field, Hperp and Hpara. For temperatures close to Tc (in the critical fluctuation region) we observed Mperp(Hperp,Hpara) Mperp(Hperp,0) and Mpara(Hperp,Hpara)~0, as expected for an extremely anisotropic material. However, deviations from this behavior are observed at lower temperatures in the London region. In particular, the Mperp amplitude under a constant Hperp decreases on increasing Hpara. In turn, in spite of the experimental uncertainties affecting Mpara (mainly associated with the rotating sample holder), its amplitude under a constant Hpara becomes observable on increasing Hperp. Both effects lead to an angular slippage of the Magnetization Vector \vec M from the c crystallographic axis when the applied magnetic field is tilted from that axis. The Mperp behavior is phenomenologically explained in the framework of Lawrence-Doniach approaches for single layered superconductors by just assuming a slight angular dependence of the so-called vortex structure constant. However, the observed Mpara is orders of magnitude larger than expected, a fact which is related to the multilayered nature of the compound studied. Our present results also directly affect the interpretation of recent measurements of the magnetic torque in other extremely anisotropic high-Tc cuprates.
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Magnetization Vector in the reversible region of the highly anisotropic cuprate superconductor Tl2Ba2Ca2Cu3O10: Anisotropy factor and the role of two-dimensional vortex fluctuations
Physical Review B, 2010Co-Authors: Jesús Mosqueira, R. I. Rey, Félix VidalAbstract:By using a high quality Tl2Ba2Ca2Cu3O10 (Tl-2223) single crystal as an example, the Magnetization Vector was probed in the reversible region of highly anisotropic cuprate superconductors. For that, we have measured its components along and transverse to the applied magnetic field for different crystal orientations. The analysis shows that the angular dependence of the perpendicular component of the Magnetization Vector follows the one predicted by a London-like approach which includes a contribution associated with the thermal fluctuations of the 2D vortex positions. For the Tl-2223 crystal studied here, a lower bound for the anisotropy factor was estimated to be about 190.
R. I. Rey - One of the best experts on this subject based on the ideXlab platform.
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angular dependence of the fluctuation Magnetization Vector above the superconducting transition of a highly anisotropic high tc cuprate
arXiv: Superconductivity, 2013Co-Authors: R. I. Rey, N. Cotón, J. D. Dancausa, J. M. Doval, A. Wahl, M. Tello, J Mosqueira, A Ramosalvarez, Félix VidalAbstract:In highly anisotropic cuprate superconductors it is generally accepted that the reversible Magnetization Vector, M, is essentially perpendicular to the superconducting CuO2 layers in a wide range of crystal orientations with respect to the applied magnetic field, H. In a recent work [J. Mosqueira et al., Phys. Rev. B 84, 134504 (2011)] it is shown, however, that the dependence of M on the H orientation in the reversible mixed state of a high-quality Tl-based cuprate presents a notable deviation from this behavior. Here we extend these measurements to the fluctuation region above Tc, in order to check whether the above mentioned effect is also present.
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Angular Dependence of the Fluctuation Magnetization Vector Above the Superconducting Transition of a Highly Anisotropic High-Tc Cuprate
Journal of Superconductivity and Novel Magnetism, 2012Co-Authors: R. I. Rey, Jesús Mosqueira, N. Cotón, J. D. Dancausa, J. M. Doval, A. Ramos-Álvarez, A. Wahl, M. Tello, Félix VidalAbstract:In highly anisotropic cuprate superconductors it is generally accepted that the reversible Magnetization Vector, \(\vec{M}\), is essentially perpendicular to the superconducting CuO2 layers in a wide range of crystal orientations with respect to the applied magnetic field, \(\vec{H}\). In a recent work (Mosqueira et al. in Phys. Rev. B 84:134504, 2011) it is shown, however, that the dependence of \(\vec{M}\) on the \(\vec{H}\) orientation in the reversible mixed state of a high-quality Tl-based cuprate presents a notable deviation from this behavior. Here we extend these measurements to the fluctuation region above Tc, in order to check whether the above-mentioned effect is also present.
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Angular slippage from the crystallographic c axis of the reversible Magnetization Vector in a tilted crystal of a highly anisotropic cuprate superconductor
Physical Review B, 2011Co-Authors: Jesús Mosqueira, R. I. Rey, A. Wahl, Félix VidalAbstract:The Magnetization Vector \vec M was measured in the reversible region of the mixed state of a high quality Tl2Ba2Ca2Cu3O10 single crystal as a function of temperature and for different magnetic field amplitudes and orientations. These measurements allowed to study the \vec M components perpendicular and parallel to the CuO2 layers (Mperp and Mpara, respectively) under arbitrary values for the corresponding components of the applied magnetic field, Hperp and Hpara. For temperatures close to Tc (in the critical fluctuation region) we observed Mperp(Hperp,Hpara) Mperp(Hperp,0) and Mpara(Hperp,Hpara)~0, as expected for an extremely anisotropic material. However, deviations from this behavior are observed at lower temperatures in the London region. In particular, the Mperp amplitude under a constant Hperp decreases on increasing Hpara. In turn, in spite of the experimental uncertainties affecting Mpara (mainly associated with the rotating sample holder), its amplitude under a constant Hpara becomes observable on increasing Hperp. Both effects lead to an angular slippage of the Magnetization Vector \vec M from the c crystallographic axis when the applied magnetic field is tilted from that axis. The Mperp behavior is phenomenologically explained in the framework of Lawrence-Doniach approaches for single layered superconductors by just assuming a slight angular dependence of the so-called vortex structure constant. However, the observed Mpara is orders of magnitude larger than expected, a fact which is related to the multilayered nature of the compound studied. Our present results also directly affect the interpretation of recent measurements of the magnetic torque in other extremely anisotropic high-Tc cuprates.
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Magnetization Vector in the reversible region of the highly anisotropic cuprate superconductor Tl2Ba2Ca2Cu3O10: Anisotropy factor and the role of two-dimensional vortex fluctuations
Physical Review B, 2010Co-Authors: Jesús Mosqueira, R. I. Rey, Félix VidalAbstract:By using a high quality Tl2Ba2Ca2Cu3O10 (Tl-2223) single crystal as an example, the Magnetization Vector was probed in the reversible region of highly anisotropic cuprate superconductors. For that, we have measured its components along and transverse to the applied magnetic field for different crystal orientations. The analysis shows that the angular dependence of the perpendicular component of the Magnetization Vector follows the one predicted by a London-like approach which includes a contribution associated with the thermal fluctuations of the 2D vortex positions. For the Tl-2223 crystal studied here, a lower bound for the anisotropy factor was estimated to be about 190.
Amlan J. Pal - One of the best experts on this subject based on the ideXlab platform.
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Spin-Polarized Scanning Tunneling Spectroscopy of Diluted Magnetic Semiconductor Quantum Dots
The Journal of Physical Chemistry C, 2014Co-Authors: Sudipto Chakrabarti, Amlan J. PalAbstract:We have formed ultrathin films of cobalt-doped ZnO quantum dots (QDs), aligned their magnetic domains, and recorded spin-polarized scanning tunneling spectroscopy (SP-STS) with a nickel tip whose Magnetization Vector was also aligned. From the SP-STS, we have calculated normalized density of states (NDOS) of the diluted magnetic semiconductor (DMS) QDs. We have observed that the intensity of peaks in NDOS spectra has depended on the mutual orientation of the Magnetization Vectors of the tip of the scanning tunneling microscope (STM) and the domains of the QDs. A higher intensity in the NDOS spectrum is observed in tip–QD systems having their domains aligned parallel to each other as compared to their antiparallel configuration. We have performed a range of control experiments to validate the observation. We hence infer that the orientation of the Magnetization Vector or the magnetic state of ferromagnetic QDs relative to that of the tip of a STM can be read or probed by recording SP-STS.
Vladimir G. Shavrov - One of the best experts on this subject based on the ideXlab platform.
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Forced Nonlinear Precession of the Second-Order Magnetization in a Magnetoelastic Material
Journal of Communications Technology and Electronics, 2019Co-Authors: V. S. Vlasov, M. S. Kirushev, Vladimir G. Shavrov, Vladimir I. ShcheglovAbstract:Nonlinear precession of the second-order Magnetization in a normally magnetized plate with magnetoelastic properties is analyzed. Orientational transition of the Magnetization Vector that lies in a variation of the equilibrium position of the Vector due to a variation in the magnetoelastic constant is studied. A system of equation for the equilibrium position of the Magnetization Vector relative to Magnetization components and elastic displacement is derived and solved with the aid of the Cardano method. Parametric portraits are obtained for Magnetization and elastic displacement, and the effect of magnetoelasticity on the geometrical properties is revealed using a model of potential. Models of effective fields and quadratic magnetoelastic coupling are proposed to interpret the dependence of the period of precession on the constant of magnetoelastic interaction.
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Magnetic and Elastic Vibrations in Manganese–Zinc Spinel Crystals as the Functions of Anisotropy Constant
Physics of the Solid State, 2018Co-Authors: Leonid N. Kotov, V. S. Vlasov, P. A. Severin, D.s. Beznosikov, E. L. Kotova, Vladimir G. ShavrovAbstract:The amplitudes of magnetic and elastic vibrations for Mn0.61Zn0.35Fe2.04O4 spinel crystalline slab are calculated by solving the equations describing the magnetic and elastic dynamics. The anisotropy constants, Magnetization, second-order elastic constants and magnetoelastic coupling constants for a studied crystal are expressed as the functions of temperature. The Magnetization Vector and elastic shear components are found as the functions of the first magnetic anisotropy constant at different values of an external constant magnetic field greater than a saturation field. The procession patterns for normally and tangentially magnetized slabs are displayed for two values of the first anisotropy constant. High absolute values of the first anisotropy constant are shown to refer to reorientation of the Magnetization Vector.
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magnetic and elastic vibrations in manganese zinc spinel crystals as the functions of anisotropy constant
Physics of the Solid State, 2018Co-Authors: Leonid N. Kotov, V. S. Vlasov, P. A. Severin, D.s. Beznosikov, E. L. Kotova, Vladimir G. ShavrovAbstract:The amplitudes of magnetic and elastic vibrations for Mn0.61Zn0.35Fe2.04O4 spinel crystalline slab are calculated by solving the equations describing the magnetic and elastic dynamics. The anisotropy constants, Magnetization, second-order elastic constants and magnetoelastic coupling constants for a studied crystal are expressed as the functions of temperature. The Magnetization Vector and elastic shear components are found as the functions of the first magnetic anisotropy constant at different values of an external constant magnetic field greater than a saturation field. The procession patterns for normally and tangentially magnetized slabs are displayed for two values of the first anisotropy constant. High absolute values of the first anisotropy constant are shown to refer to reorientation of the Magnetization Vector.
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Second Order Precession in the Plate with Cubic Anisotropy and Magnetoelastic Properties
Solid State Phenomena, 2015Co-Authors: Kirushev, V. S. Vlasov, Vladimir G. Shavrov, Leonid N. Kotov, D.a. Pleshev, F.f. Asadullin, V. I. ShcheglovAbstract:The paper considers the second order precession of the Magnetization Vector in a perpendicular magnetized anisotropic ferrite plate with magnetoelastic properties. The boundaries of the precession regimes on the frequency and amplitude of the alternating field were defined. The features of the precession of the Magnetization Vector regimes associated with magnetoelastic properties were revealed.
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Forced nonlinear precession of the Magnetization Vector under the conditions of an orientation transition
Journal of Communications Technology and Electronics, 2011Co-Authors: V. S. Vlasov, Vladimir G. Shavrov, Leonid N. Kotov, V. I. ShcheglovAbstract:Forced nonlinear precession of the Magnetization Vector in a normally magnetized magnetic plate under the conditions of an orientation transition is considered. It is shown that, in the field lower than the form deMagnetization field, the variable circularly polarized field causes precession of the equilibrium position of the Magnetization Vector. It is demonstrated based on a Vector model in which the precession period of the equilibrium position is inversely proportional to the squared amplitude of the variable field and the sine of the angle of deviation of the equilibrium position of Magnetization from the constant field. It is shown that the critical parameters necessary for excitation of precession of the equilibrium position are the amplitude and frequency of the variable field. Diagrams determining domains of existence of precession of the equilibrium position for different saturation Magnetization of a magnetic plate are constructed in terms of the coordinates variable field amplitude-frequency. The role of dissipation of Magnetization oscillations in the determination of the critical parameters is elucidated. The features of precession in the presence of asymmetric excitation and in the presence of anisotropy in the plane of the plate are noted.