Download or read book Proximity Effect in Superconductor ferromagnet Systems written by Jian Zhu and published by . This book was released on 2010 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt: The proximity effect in superconductor (SC) - ferromagnet (FM) system produces many interesting phenomena due to the interplay between two competing orderings, superconductivity and ferromagnetism. This dissertation studies the influence of the orientation of magnetic moments on the superconducting transition temperature (Tc̳) in FM/SC/FM sandwiched structures. The superconducting transition temperature of a FM/SC/FM spin valve depends on the mutual orientation of the magnetic moments of the ferromagnetic layers. This phenomenon, called the spin switch effect, has been previously observed in FM/SC/FM systems as a Tc̳ difference between parallel and antiparallel configurations of the ferromagnetic layers. Both standard (TP̳c̳ TA̳P̳c̳) and inverse (TP̳c̳ TA̳P̳̳c̳) spin switch effects have been reported in different superconducting spin valve systems but the origin of the inverse spin switch effect was not understood. In this dissertation, a discovery of the coexistence of the standard and inverse spin switch effects in Ni1 Fe19 /Nb/Ni1 Fe19 /Ir25 Mn--5 spin valves is described. The measurements reveal that the inverse spin switch effect originates from dissipative flow of vortices induced by stray magnetic field of magnetostatically coupled Neel domain wall pairs in the ferromagnetic layers. This dissertation also studies the Tc̳ of FM/SC/FM sandwiched systems with noncollinear (neither parallel nor antiparallel) orientation of the magnetic moments of the ferromagnetic layers, where the odd triplet superconducting component is predicated to arise. Tc̳ in Cu48 Ni52 /Nb/Cu48 Ni52 trilayers as a function of the angle between the Cu48 Ni52 layer magnetizations is measured. The shape of the observed angular dependence ofTc̳ is in qualitative agreement with SC/FM proximity theories that account for the odd triplet component of the condensate, but large discrepancy in the magnitude is found.

Download or read book Proximity Effect in the Superconductor Ferromagnet Nb Fe Layered System written by Thorsten Mühge and published by . This book was released on 1997 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proximity Effect in Ferromagnet superconductor Hybrid Systems written by Ion Cătălin Moraru and published by . This book was released on 2006 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Magnetic Heterostructures written by H. Zabel and published by Springer. This book was released on 2007-10-26 with total page 373 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heterostructures consist of combinations of different materials, which are in contact through at least one interface. Magnetic heterostructures combine different physical properties which do not exist in nature. This book provides the first comprehensive overview of an exciting and fast developing field of research, which has already resulted in numerous applications and is the basis for future spintronic devices.

Download or read book Proximity and Flux Pinning Effects in Superconductor ferromagnet Hybrids written by Xavier Palermo and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Superconductor-ferromagnet hybrid systems often bring about new physics and may as well be useful to design new non-volatile, high-density memory devices for superconducting electronics.In this thesis, we study two different types of SF hybrids, each following a possible approach to memory devices, but focusing on fundamental aspects. One is about the proximity effect in oxide heterostructures. In these, triplet correlations appear, that are both superconducting and spin-polarized. These enable using effects from spintronics like GMR, but are also very dependent on interface properties. We investigated these in SFS oxide trilayers by conductance measurements. These showed oscillations which may, in part, be related to these triplet states. We also observed that interface effects affect the electronic properties of the ferromagnet, especially when that layer is thin. Another type of interaction occurs through stray magnetic fields from the domain structures. Recent theoretical proposals suggested that small swirling spin textures called skyrmions could similarly interact with superconductivity through this mechanism. We investigated such coupling in bilayers, in which the superconducting vortex dynamics dominate the transport properties. We found that the presence of skyrmions and domains alike enhances the critical current. It also leads to an unusual Hall effect in the superconducting state. Most of these properties can be explained qualitatively in terms of vortex pinning and guided motion.

Download or read book Investigation of Magnetic Proximity Effect in Ferromagnet superconductor Thin Films by Low Temperature Magneto Optical Kerr Effect Measurement written by David A. Christiansen and published by . This book was released on 2012 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: A room temperature Magneto Optical Kerr Effect (MOKE) experimental setup was expanded to improve performance and integrated with a liquid Helium cryogenic system. Ferromagnetic/superconductor hybrid systems have recently been intensively studied due to their interesting proximity effect and the possible applications such as a current switching device. Most of previous work focused on the superconducting property change due to the presence of the ferromagnet but not much research of the magnetic property change due to the superconducting transition has been done. Using the extended MOKE setup, magnetization from the top ferromagnetic layer can be measured below and above the critical temperature of the superconducting thin film layer. Temperatures as low as 4.2K were achieved and the magnetization with respect to applied magnetic field of a Permalloy/Niobium (Py/Nb) thin film was measured at 295K, 11K, and 4.2K. Coercivity increased as temperature decreased. A magnetization measurement with constant applied magnetic field was also performed with a temperature sweep passing the superconducting transition. However, due to temperature instability it was difficult to compare the magnetization above and below Tc of the Nb. Both hysteresis loops above and below the superconducting critical temperature were measured to be similar within the measurement error and have a coercivity of 160 ±16 Oe. Reasons for not detecting a magnetization change due to the superconductor could be either due to sample heating, thermometer calibration, the limited accuracy of measuring the coercivity in this sample, or the change due to the SC may be smaller or not exist.

Download or read book Inverse Proximity Effect in Superconductor ferromagnet Bilayer Structures written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proximity Effects in Superconductor Ferromagnet Structures written by and published by . This book was released on 2008 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Thermodynamics Triplets and Transport written by Paul H. Barsic and published by . This book was released on 2007 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Superconductor ferromagnet Proximity Effect Studied by Scanning Tunneling Microscopy written by Yoav Kalcheim and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Proximity Effect in High Tc Superconductor ferromagnet Bilayers Studied by Scanning Tunneling Spectroscopy written by Itay Asulin and published by . This book was released on 2009 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Study of the Influence of Domain Walls in the Superconductor Ferromagnet Proximity Effect written by Edgar Javier Patiño and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Superconducting Critical Temperature of Inhomogeneous Magnetic Proximity Systems written by Adam Moke and published by . This book was released on 2013 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The proximity effect is investigated for ferromagnet-superconductor bilayers through the suppression of the superconducting critical temperature. We consider both homogeneous and inhomogeneous ferromagnets to study the effect of triplet pairing correlations on the critical temperature. The inhomogeneous ferromagnet we work with is an exchange spring that provides a tunable magnetization profile. The critical temperature is calculated as a function of ferromagnet thickness, spin flip scattering time, and magnetization profile of an exchange spring. An attempt is made to connect the behavior of the critical temperature with that of the superconducting order parameter.

Download or read book Interaction of Superconductivity and Ferromagnetism in YBCO LCMO Heterostructures written by Soltan Soltan and published by Cuvillier Verlag. This book was released on 2005 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Interplay of Proximity Effects in Superconductor ferromagnet Heterostructures written by Annika Stellhorn and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Numerical Modeling of the Singlet Proximity Effect in a Superconductor ferromagnet Trilayer written by Adam C. Richie-Halford and published by . This book was released on 2010 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: We investigate superconductor-insulator-ferromagnet-superconductor Josephson junctions using the quasiclassical Green's functional theory in the "dirty limit," where the elastic scattering length [cursive l] is much shorter than the characteristic decay length in the ferromagnet. We manipulate the governing Usadel equations for entry into numerical analysis and develop a numerical model to explore the behavior of the superconducting Green's functions in the trilayer, avoiding the linearizing approximation usually found in the literature. We then review the results of the numerical calculation for the behavior of the Green's function under the variation of the ferromagnet thickness [italicized d][subscript f], the ferromagnet's internal magnetization strength [italicized h], the strength of the proximity effect [gamma], and the interface transparency [gamma][subscript b]. These results are compared to analytical, numerical, and experimental results in the existing literature. We close with suggestions for future research.

Download or read book The Oxford Handbook of Small Superconductors written by A. V. Narlikar and published by Oxford University Press. This book was released on 2017 with total page 641 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mesoscopic superconductors achieve a level of smallness that reveals the dominance of strange quantum effects. In a world driven by the miniaturization of electronic device technology, small superconductors acquire great relevance and timeliness for the development of ground breaking novel quantum devices.