References of "Vanderbemden, Philippe"
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See detailMagnetocaloric effect and magnetic properties of Tb0.9Sn0.1MnO3
Fabris, Frederik Wolff; Pekala, Marek; Drozd, V. et al

in Journal of Applied Physics (2007), 101(10), 103904

The magnetocaloric effect in magnetic materials is of great interest nowadays. In this article we present an investigation about the magnetic properties near the magnetic transition in a polycrystalline ... [more ▼]

The magnetocaloric effect in magnetic materials is of great interest nowadays. In this article we present an investigation about the magnetic properties near the magnetic transition in a polycrystalline sample of a manganite Tb0.9Sn0.1MnO3. Particularly, we are interested in describing the nature of the magnetic interactions and the magnetocaloric effect in this compound. The temperature dependence of the magnetization was measured to determine the characteristics of the magnetic transition and the magnetic entropy change was calculated from magnetization curves at different temperatures. The magnetic solid is paramagnetic at high temperatures. We observe a dominant antiferromagnetic interaction below T-n=38 K for low applied magnetic fields; the presence of Sn doping in this compound decreases the Neel temperature of the pure TbMnO3 system. A drastic increase in the magnetization as a function of temperature near the magnetic transition suggests a strong magnetocaloric effect. We found a large magnetic entropy change Delta S-M(T) of about -4 J/kg K at µ0H=3 T. We believe that the magnetic entropy change is associated with the magnetic transition and we interpret it as due to the coupling between the magnetic field and the spin ordering. This relatively large value and broad temperature interval (about 35 K) of the magnetocaloric effect make the present compound a promising candidate for magnetic refrigerators at low temperatures. (c) 2007 American Institute of Physics. [less ▲]

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See detailMagnetic and transport properties investigation of rare-earth compounds with orthorhombic structures
Lovchinov, V.; Apostolov, A.; Dimitrov, D. et al

in Journal of Optoelectronics and Advanced Materials [= JOAM] (2007), 9(2), 460-463

The structural, magnetic, magnetoelectric, and ferroelectric properties of a series of monocrystals with perovskite structures have been examined. The investigations were carried out in the temperature ... [more ▼]

The structural, magnetic, magnetoelectric, and ferroelectric properties of a series of monocrystals with perovskite structures have been examined. The investigations were carried out in the temperature range 2-800 K and at magnetic fields up to 14 T. The existence of giant magnetoresistance (GMR) for some samples, a giant magnetostiction effect for others and the presence of multiphase ferroelectric states were demonstrated. Various possibilities for practical applications are discussed. [less ▲]

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See detailInfluence of thermal treatment on YBa2Cu3O7-x thick films prepared by electrophoretic deposition on Ni and Ag substrates
Dusoulier, Laurent; Denis, Samuel; Dirickx, Michel et al

in Materials Research Society Symposium Proceedings (2007), 1001E

We have studied the sintering parameters of YBa2Cu3O7-x (YBCO) coatings produced by electrophoretic deposition (EPD) on Ag and Ni substrates. The maximal sintering temperature is ~ 930°C due to partial ... [more ▼]

We have studied the sintering parameters of YBa2Cu3O7-x (YBCO) coatings produced by electrophoretic deposition (EPD) on Ag and Ni substrates. The maximal sintering temperature is ~ 930°C due to partial melting and chemical contamination for Ag and Ni substrates respectively. Increasing the sintering duration does not improve significantly the densification. When Ar sintering atmosphere is used, the coating density is strongly increased on Ag substrates while adhesion is poor on Ni substrates. The Ar-sintered YBCO coating deposited on planar Ag substrate displays a significant magnetic shielding effect for low frequency applied magnetic induction. [less ▲]

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See detailElectrical transport and percolation in magnetoresistive manganite/insulating oxide composites: Case of La0.7Ca0.3MnO3/Mn3O4
Vertruyen, Bénédicte ULg; Cloots, Rudi ULg; Ausloos, Marcel ULg et al

in Physical Review. B (2007), 75(16), 165112

We report the results of electrical resistivity measurements carried out on well-sintered La0.7Ca0.3MnO3/Mn3O4 composite samples with almost constant composition of the magnetoresistive manganite phase ... [more ▼]

We report the results of electrical resistivity measurements carried out on well-sintered La0.7Ca0.3MnO3/Mn3O4 composite samples with almost constant composition of the magnetoresistive manganite phase (La0.7Ca0.3MnO3). A percolation threshold (phi c) occurs when the La0.7Ca0.3MnO3 volume fraction is ~ 0.19. The dependence of the electrical resistivity rho as a function of La0.7Ca0.3MnO3 volume fraction fLCMO can be described by percolationlike phenomenological equations. Fitting the conducting regime (fLCMO > phic) by the percolation power law rho # (fLCMO - phic)^(-t) returns a critical exponent value of 2.0±0.2 at room temperature and 2.6±0.2 at 5 K. The increase of t is ascribed to the influence of the grain boundaries on the electrical conduction process at low temperature. (C) 2007 The American Physical Society. [less ▲]

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See detailMagnetic shielding properties of high-temperature superconducting tubes subjected to axial fields
Denis, Samuel ULg; Dusoulier, Laurent; Dirickx, Michel ULg et al

in Superconductor Science and Technology (2007), 20(3), 192-201

We have experimentally studied the magnetic shielding properties of a cylindrical shell of BiPbSrCaCuO subjected to low frequency AC axial magnetic fields. The magnetic response has been investigated as a ... [more ▼]

We have experimentally studied the magnetic shielding properties of a cylindrical shell of BiPbSrCaCuO subjected to low frequency AC axial magnetic fields. The magnetic response has been investigated as a function of the dimensions of the tube, the magnitude of the applied field and the frequency. These results are explained quantitatively by employing the method of Brandt ( 1998 Phys. Rev. B 58 6506) with a Jc( B) law appropriate for a polycrystalline material. Specifically, we observe that the applied field can sweep into the central region either through the thickness of the shield or through the opening ends, the latter mechanism being suppressed for long tubes. For the first time, we systematically detail the spatial variation of the shielding factor ( the ratio of the applied field over the internal magnetic field) along the axis of a high-temperature superconducting tube. The shielding factor is shown to be constant in a region around the centre of the tube, and to decrease as an exponential in the vicinity of the ends. This spatial dependence comes from the competition between two mechanisms of field penetration. The frequency dependence of the shielding factor is also discussed and shown to follow a power law arising from the finite creep exponent n. [less ▲]

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See detailField penetration into hard type-II superconducting tubes: effects of a cap, a non-superconducting joint, and non-uniform superconducting properties
Denis, Samuel ULg; Dirickx, Michel ULg; Vanderbemden, Philippe ULg et al

in Superconductor Science and Technology (2007), 20(5), 418-427

Using the numerical method of Brandt (1998 Phys. Rev. B 58 6506), we study the penetration of a uniform magnetic field that is gradually applied parallel to the axis of finite type-II superconducting ... [more ▼]

Using the numerical method of Brandt (1998 Phys. Rev. B 58 6506), we study the penetration of a uniform magnetic field that is gradually applied parallel to the axis of finite type-II superconducting tubular samples with strong pinning. This study is carried out in view of designing low-frequency magnetic shields by exploiting the diamagnetic properties of type-II superconductors. First, we compare the field penetration into open and closed tubes. For long tubes (length larger than three times the outer diameter), we show that a cap weakly affects the maximum magnetic induction that can be shielded, but greatly increases the region over which the field is nearly uniform. When the length of the tube is shorter, both the maximum shieldable magnetic induction and the uniformity of the field attenuation are enhanced by closing the tube. We also show that making a hole in the cap, which is often necessary for applications, does not greatly affect the shielding properties provided the diameter of the hole is small compared to that of the tube (hole diameter smaller than a quarter of the outer tube diameter). In view of designing large size magnetic shields, superconducting tubes of finite size need to be joined together. We therefore examine in a second part how the presence of a non-superconducting joint between the tubes affects the shielding efficiency. It is shown that the effect of a joint depends upon its position along the tube axis and strongly increases with its size. Third, we study how non-uniform superconducting properties affect the shielding capabilities. [less ▲]

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See detailElectrical transport and magnetic properties of Mn3O4-La0.7Ca0.3MnO3 ceramic composites prepared by a one-step spray-drying technique
Vertruyen, Bénédicte ULg; Fagnard, Jean-François ULg; Vanderbemden, Philippe ULg et al

in Journal of the European Ceramic Society (2007), 27(13-15), 3923-3926

La0.7Ca0.3MnO3/Mn3O4 composites can be synthesized in one step by thermal treatment of a spray-dried precursor, instead of mixing pre-synthesized powders. Another advantage of this composite system is ... [more ▼]

La0.7Ca0.3MnO3/Mn3O4 composites can be synthesized in one step by thermal treatment of a spray-dried precursor, instead of mixing pre-synthesized powders. Another advantage of this composite system is that a long sintering step can be used without leading to significant modification of the manganite composition. The percolation threshold is reached at ~ 20 vol% of manganite phase. The 77 K low field magnetoresistance is enhanced to ~ 11 % at 0.15 T when the composition is close to the percolation threshold. (c) 2007 Elsevier Ltd. All rights reserved. [less ▲]

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See detailBehavior of bulk high-temperature superconductors of finite thickness subjected to crossed magnetic fields: Experiment and model
Vanderbemden, Philippe ULg; Hong, Z.; Coombs, T. A. et al

in Physical Review. B (2007), 75(17), 174515

Crossed-magnetic-field effects on bulk high-temperature superconductors have been studied both experimentally and numerically. The sample geometry investigated involves finite-size effects along both ... [more ▼]

Crossed-magnetic-field effects on bulk high-temperature superconductors have been studied both experimentally and numerically. The sample geometry investigated involves finite-size effects along both (crossed-)magnetic-field directions. The experiments were carried out on bulk melt-processed Y-Ba-Cu-O single domains that had been premagnetized with the applied field parallel to their shortest direction (i.e., the c axis) and then subjected to several cycles of the application of a transverse magnetic field parallel to the sample ab plane. The magnetic properties were measured using orthogonal pickup coils, a Hall probe placed against the sample surface, and magneto-optical imaging. We show that all principal features of the experimental data can be reproduced qualitatively using a two-dimensional finite-element numerical model based on an E-J power law and in which the current density flows perpendicularly to the plane within which the two components of magnetic field are varied. The results of this study suggest that the suppression of the magnetic moment under the action of a transverse field can be predicted successfully by ignoring the existence of flux-free configurations or flux-cutting effects. These investigations show that the observed decay in magnetization results from the intricate modification of current distribution within the sample cross section. The current amplitude is altered significantly only if a field-dependent critical current density Jc(B) is assumed. Our model is shown to be quite appropriate to describe the cross-flow effects in bulk superconductors. It is also shown that this model does not predict any saturation of the magnetic induction, even after a large number (~ 100) of transverse field cycles. These features are shown to be consistent with the experimental data. (C) The American Physical Society. [less ▲]

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See detailLiMn2-xTixO4 spinel-type compounds (x <= 1): Structural, electrical and magnetic properties
Krins, Natasha ULg; Hatert, Frédéric ULg; Traina, Karl ULg et al

in Solid State Ionics (2006), 177(11-12), 1033-1040

LiMn2-xTixO4 compounds with 0.5 =<x =< 1 were prepared by solid state reaction and Pechini technique. Powder X-ray diffraction showed that all samples crystallize with the spinel crystal structure (S.G ... [more ▼]

LiMn2-xTixO4 compounds with 0.5 =<x =< 1 were prepared by solid state reaction and Pechini technique. Powder X-ray diffraction showed that all samples crystallize with the spinel crystal structure (S.G. Fd3m). The cubic unit-cell parameter increases with the Ti content. The influence of the Ti content and cationic distribution on the magnetic properties of the compounds was studied by measuring the temperature and magnetic field dependences of the magnetization: substitution by non-magnetic d(0) Ti4+ ions appeared to weaken the magnetic interactions between the manganese ions. The electrical properties of LiMnTiO4 were studied by AC impedance spectroscopy and DC polarisation measurements, which revealed the electronic character of the conduction process. (c) 2006 Elsevier B.V. All rights reserved. [less ▲]

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See detailCharacterisation of the magnetic shielding properties of YBaCuO thick films prepared by electrophoretic deposition on silver substrates
Denis, Samuel; Grenci, G.; Dusoulier, Laurent et al

in Journal of Physics: Conference Series (2006), 43

This communication reports experimental results on the superconducting properties of YBaCuO thick films prepared by electrophoretic deposition on silver substrates. The magnetic shielding properties of ... [more ▼]

This communication reports experimental results on the superconducting properties of YBaCuO thick films prepared by electrophoretic deposition on silver substrates. The magnetic shielding properties of the coatings were characterised by various methods. First, the electrical resistance and the transport critical current density, Jc, were determined. Our coatings exhibit a superconducting transition at a temperature of 90 K. Next, shielding characterisations were carried out at 77 K for samples having either a slab or a cylindrical geometry. In both cases, the frequency of the applied magnetic field was 103 Hz; the field behind the shielding wall was measured by a pick-up coil connected to a lock-in amplifier. In the case of cylindrical samples and for an applied induction lower than 1 G, the field inside the shielding enclosure is reduced by a factor greater than 106 (i.e. 120 dB) with respect to the applied field. [less ▲]

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See detailYBa2Cu3O(7-delta) thick films on Ag prepared by the electrophoretic deposition technique
Dusoulier, Laurent; Denis, Samuel; Fagnard, Jean-François ULg et al

in Journal of Physics: Conference Series (2006), 43

YBa2Cu3O7-δ thick films have been deposited onto Ag substrates by the Electrophoretic Deposition (EPD) technique. Different microstructures and electrical behaviours were observed depending on the ... [more ▼]

YBa2Cu3O7-δ thick films have been deposited onto Ag substrates by the Electrophoretic Deposition (EPD) technique. Different microstructures and electrical behaviours were observed depending on the starting powder. Coatings prepared from commercial powder displayed significant porosity and the superconducting transition width was found to be magnetic-field dependent. Films produced from home-made coprecipitated powder are denser but contain some secondary phases. No dependence of the resistive transition as a function of magnetic field (H ≤ 20 Oe) was observed in that case. [less ▲]

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See detailStudy of thermal effects in bulk RE-BCO superconductors submitted to a variable magnetic field
Laurent, Philippe; Fagnard, Jean-François ULg; Mathieu, J.-P. et al

in Journal of Physics: Conference Series (2006), 43

When bulk RE-BCO superconductors are used as permanent magnets in engineering applications, they are likely to experience transient variations of the applied magnetic field. The resulting vortex motion ... [more ▼]

When bulk RE-BCO superconductors are used as permanent magnets in engineering applications, they are likely to experience transient variations of the applied magnetic field. The resulting vortex motion may cause a significant temperature increase. As a consequence the initial trapped flux is reduced. In the present work, we first focus on the cause of a temperature increase. The temperature distribution within a superconducting finite cylinder subjected to an alternating magnetic field is theoretically predicted. Results are compared to experimental data obtained by two temperature sensors attached to a bulk YBCO pellet. Second, we consider curative methods for reducing the effect of heat flux on the temperature increase. Hall-probe mappings on YBCO samples maintained out of the thermal equilibrium are performed for two different morphologies : a plain single domain and a single domain with a regularly spaced hole array. The drilled single-domain displays a trapped induction which is weakly affected by the local heating while displaying a high trapped field. [less ▲]

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See detailUse of a High-Temperature Superconducting Coil for Magnetic Energy Storage
Fagnard, Jean-François ULg; Crate, David; Jamoye, Jean-François et al

in Institute of Physics Conference Series (2006), 43

A high temperature superconducting magnetic energy storage device (SMES) has been realised using a 350 m-long BSCCO tape wound as a ''pancake'' coil. The coil is mounted on a cryocooler allowing ... [more ▼]

A high temperature superconducting magnetic energy storage device (SMES) has been realised using a 350 m-long BSCCO tape wound as a ''pancake'' coil. The coil is mounted on a cryocooler allowing temperatures down to 17.2 K to be achieved. The temperature dependence of coil electrical resistance R(T) shows a superconducting transition at T = 102.5 K. Measurements of the V(I) characteristics were performed at several temperatures between 17.2 K and 101.5 K to obtain the temperature dependence of the critical current (using a 1 uV/cm criterion). Critical currents were found to exceed 100 A for T < 30 K. An electronic DC-DC converter was built in order to control the energy flow in and out of the superconducting coil. The converter consists of a MOS transistor bridge switching at a 80 kHz frequency and controlled with standard Pulse Width Modulation (PWM) techniques. The system was tested using a 30 V squared wave power supply as bridge input voltage. The coil current, the bridge input and output voltages were recorded simultaneously. Using a 10 A setpoint current in the superconducting coil, the whole system (coil + DC-DC converter) can provide a stable output voltage showing uninterruptible power supply (UPS) capabilities over 1 s. [less ▲]

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See detailTexturation of YBa2Cu3O7-delta thick films by electrophoretic deposition under magnetic field
Dusoulier, Laurent; Denis, Samuel ULg; Nutal, Nicolas ULg et al

in Key Engineering Materials [=KEM] (2006), 314

YBa2Cu3O7-delta coatings were deposited by electrophoretic deposition (EPD) onto Ni substrates. Particles of different sizes and shapes were used in order to study the influence of the powder ... [more ▼]

YBa2Cu3O7-delta coatings were deposited by electrophoretic deposition (EPD) onto Ni substrates. Particles of different sizes and shapes were used in order to study the influence of the powder microstructure on the film density. Texturation of the thick films was induced by application of a magnetic field during the electrophoretic deposition. X-ray diffraction analysis has clearly shown preferred c-axis alignment of the YBa2Cu3O7-delta films along the direction normal to the substrate surface. Scanning electron microscopy and optical polarised light microscopy were used to characterise the microstructure of the coatings, revealing a nonrandom platelets organisation. [less ▲]

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See detailPreparation of YBa2Cu3O7-x superconducting thick films by the electrophoretic deposition method
Dusoulier, Laurent; Denis, Samuel ULg; Vanderbemden, Philippe ULg et al

in Journal of Materials Science (2006), 41(24), 8109-8114

YBa2Cu3O7-x thick films have been realised by the Electrophoretic Deposition method (EPD). The influence of several parameters (powder and iodine concentrations in the suspension, applied voltage and ... [more ▼]

YBa2Cu3O7-x thick films have been realised by the Electrophoretic Deposition method (EPD). The influence of several parameters (powder and iodine concentrations in the suspension, applied voltage and deposition time) on the EPD process has been studied by measuring the conductivity of the suspension and the amount of YBa2Cu3O7-x particles deposited on the electrode. Superconducting coatings onto silver substrates have been produced by a multilayer process during different deposition times. The highest critical current density value of these coatings measured by the four-point probe method is about 10^3 A/cm^2 (77 K), in a suitable range for magnetic shielding applications. [less ▲]

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See detailSpin-cluster effect and lattice-deformation-induced Kondo effect, spinglass freezing, and strong phonon scattering in La0.7Ca0.3Mn1-xCrxO3
Wu, Bai-Mei; Li, Bo; Zhen, Wei-Hua et al

in Journal of Applied Physics (2005), 97(10, Part 1), 103908

Besides the Kondo effect observed in dilute magnetic alloys, the Cr-doped perovskite manganate compounds La0.7Ca0.3Mn1-xCrxO3 also exhibit Kondo effect and spin-glass freezing in a certain composition ... [more ▼]

Besides the Kondo effect observed in dilute magnetic alloys, the Cr-doped perovskite manganate compounds La0.7Ca0.3Mn1-xCrxO3 also exhibit Kondo effect and spin-glass freezing in a certain composition range. An extensive investigation for the La0.7Ca0.3Mn1-xCrO3 (x=0.01, 0.05, 0.10, 0.3, 0.6, and 1.0) system on the magnetization and ac susceptibility, the resistivity and magnetoresistance, as well as the thermal conductivity is done at low temperature. The spin-glass behavior has been confirmed for these compounds with x=0.05, 0.1, and 0.3. For temperatures above T-f (the spin-glass freezing temperature) a Curie-Weiss law is obeyed. The paramagnetic Curie temperature 0 is dependent on Cr doping. Below T-f there exists a Kondo minimum in the resistivity. Colossal magnetoresistance has been observed in this system with Cr concentration up to x=0.6. We suppose that the substitution of Mn with Cr dilutes Mn ions and changes the long-range ferromagnetic order of La0.7Ca0.3MnO3. These behaviors demonstrate that short-range ferromagnetic correlation and fluctuation exist among Mn spins far above T-f. Furthermore, these interactions are a precursor of the cooperative freezing at T-f. The "double bumps" feature in the resistivity-temperature curve is observed in compounds with x= 0.05 and 0.1. The phonon scattering is enhanced at low temperatures, where the second peak of double bumps comes out. The results indicate that the spin-cluster effect and lattice deformation induce Kondo effect, spin-glass freezing, and strong phonon scattering in mixed perovskite La0.7Ca0.3Mn1-xCrO3. (c) 2005 American Institute of Physics. [less ▲]

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See detailSilver paint as a soldering agent for DyBaCuO single-domain welding
Mathieu, Jean-Philippe; Fagnard, Jean-François ULg; Laurent, Philippe ULg et al

in Superconductor Science and Technology (2005), 18(4), 508-512

Silver paint has been tested as a soldering agent for DyBaCuO 4 single-domain welding. Junctions have been manufactured on Dy-Ba-Cu-O single domains cut either along planes parallel to the c-axis IT or ... [more ▼]

Silver paint has been tested as a soldering agent for DyBaCuO 4 single-domain welding. Junctions have been manufactured on Dy-Ba-Cu-O single domains cut either along planes parallel to the c-axis IT or along the ab-planes. Microstructural and superconducting characterizations of the samples have been performed. For both types of junctions, the microstructure in the joined area is very clean: no secondary phase or Ag particle segregation has been observed. Electrical and magnetic measurements for all configurations of interest are reported (rho(T) curves, and Hall probe mapping). The narrow resistive superconducting transition reported for all configurations shows that the artificial junction does not affect significantly the measured superconducting properties of the material. [less ▲]

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See detailSuperconducting nanostructured magnesium diboride
Kalaydjiev, K.; Lovchinov, V.; Dimitrov, D. et al

in Journal of Optoelectronics and Advanced Materials [= JOAM] (2005), 7(1), 423-426

Like conventional superconductors, MgB2 is a phonon-mediated superconductor with a relatively long coherence length. Its properties make the prospects for fabricating reproducible uniform Josephson ... [more ▼]

Like conventional superconductors, MgB2 is a phonon-mediated superconductor with a relatively long coherence length. Its properties make the prospects for fabricating reproducible uniform Josephson junctions, the fundamental element of superconducting circuits, much more favorable for MgB2 than for high-temperature superconductors. Here, we report bulk superconductivity in nanophase MgB2, using a two-step technique of mechanically activated sjavascript:$('next-but').click();elf-propagated high-temperature synthesis(MASHS). The conditions of synthesis and some properties of the product (structure, susceptibility, resistivity) were studied. It was shown that a single-phase product was obtained after 2 hours of intense mechanical treatment of reagents (Mg and B powders), and MASHS induced at 30 A cm(-2). [less ▲]

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See detailSpin glass behaviour and spin-dependent scattering in La0.7Ca0.3Mn0.9Cr0.1O3 perovskites
Wu, B. M.; Ausloos, Marcel ULg; Du, Y. L. et al

in Chinese Physics Letters (2005), 22(3), 686-689

The magnetic, electrical and thermal transport properties of the perovskite La0.7Ca0.3Mn0.9Cr0.1O3 have been investigated by measuring dc magnetization, ac susceptibility, the magnetoresistance and ... [more ▼]

The magnetic, electrical and thermal transport properties of the perovskite La0.7Ca0.3Mn0.9Cr0.1O3 have been investigated by measuring dc magnetization, ac susceptibility, the magnetoresistance and thermal conductivity in the temperature range of 5-300 K. The spin glass behaviour with a spin freezing temperature of 70 K has been well confirmed for this compound, which demonstrates the coexistence and competition between ferromagnetic and antiferromagnetic clusters by the introduction of Cr. Colossal magnetoresistance has been observed over the temperature range investigated. The introduction of Cr causes the "double-bump" feature in electrical resistivity rho(T). Anomalies on the susceptibility and the thermal conductivity associated with the double-bumps in rho(T) are observed simultaneously. The imaginary part of ac susceptibility shows a sharp peak at the temperature of insulating-metallic transition where the first resistivity bump was observed, but it is a deep-set valley near the temperature where the second bump in rho(T) emerges. The thermal conductivity shows an increase below the temperature of the insulating metallic transition, but the phonon scattering is enhanced accompanying the appearance of the second peak of double-bumps in rho(T). We relate those observed in magnetic and transport properties of La0.7Ca0.3Mn0.9Cr0.1O3 to the spin-dependent scattering. The results reveal that the spin-phonon interaction may be of more significance than the electron (charge)-phonon interaction in the mixed perovskite system. [less ▲]

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See detailMagneto-transport characterization of Dy123 monodomain superconductors
Pekala, Marek; Mucha, Jan ULg; Vanderbemden, Philippe ULg et al

in Applied Physics A : Materials Science & Processing (2005), 81(5), 1001-1007

We consider textured materials of the DyBa2Cu3O7 type seeded with a Nd123 seed as initiator. They are grown with an excess 20% Dy211 phase on a Dy2O3 substrate. We report chemical characterization ... [more ▼]

We consider textured materials of the DyBa2Cu3O7 type seeded with a Nd123 seed as initiator. They are grown with an excess 20% Dy211 phase on a Dy2O3 substrate. We report chemical characterization, electrical resistivity, thermoelectric power and thermal conductivity over a broad temperature range as a function of an applied magnetic field up to 6 T. We show that specific features appear in the magneto-thermal transport properties, different in these materials from those found in single crystals and polycrystalline samples. We propose that two vortex regimes can be distinguished in the mixed phase, due to the intrinsic microstructure. We calculate the viscosity, entropy and figure of merit of the samples. [less ▲]

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