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We have studied the diffusion coefficient of hot electrons in GaN crystals under moderate electric (1...10 kV/cm) and magnetic (1...4 T) fields. Two configurations, parallel and crossed fields, have been analyzed. The study was carried out for compensated bulk- like GaN samples for various lattice temperatures (30...300 K) and impurity concentrations (10 16 ...10 17 cm -3 ). We found that at low lattice temperatures and low impurity concentrations, electric-field dependences of the transversal-to-current components of the diffusion tensor are non-monotonic for both configurations, while diffusion processes are mainly controlled by the magnetic field. With increasing the lattice temperature or impurity concentration, behaviour of the diffusion tensor becomes more monotonous and less affected by the magnetic field. We showed that this behaviour of the diffusion processes is caused by the distinct kinetics of hot electrons in polar semiconductors with strong electron-optical phonon coupling. We have suggested that measurements of the diffusion coefficient of electrons subjected to electric and magnetic fields facilitate identification of features of different electron transport regimes and development of more efficient devices and practical applications.

Abstract Large-scale, electrically interconnected three-dimensional (3-D) Ni crossed nanotube networks have been fabricated using an electrochemical dealloying method within the crossed nanopores of polymer host membranes. This method paves the way for the easy and cost-effective fabrication of 3-D magnetic NT networks with precise spatial arrangement and diameter and wall thickness of 10–100 nm controlled individually. The excellent control over geometrical parameters and morphological features of the Ni crossed nanotube networks leads to tunable magnetic and magneto-transport properties. Particularly, the low field magneto-transport behavior is consistent with the expected vortex-like states formed in different segments of the nanotube scaffold, whereas nucleation of domain walls at the intersection of the nanowire segments play a dominant role in the solid crossed nanowire networks counterpart. The present 3-D networks of nanomagnets are of special interest due to their potential for memory devices, computing architectures, sensing and biomedical applications.

We investigated the structural and magnetic properties of bare SrRuO3 (SRO) ultrathin films and SrRuO3/SrIrO3/SrZrO3 (SRO/SIO/SZO: RIZ) trilayer heterostructures between 10 and 80 K, by comparing macroscopic data using the magneto-optical Kerr effect (MOKE) and magneto-transport (anomalous Hall effect: AHE), with nanoscale fingerprints when applying noncontact scanning force microscopy (nc-SFM) and magnetic force microscopy (MFM). SRO and RIZ ultrathin films were epitaxially grown at 650 °C onto vicinal SrTiO3 (100) single-crystalline substrates to a nominal thickness of 4 and 4/2/2 unit cells (uc), respectively. Our correlated analysis allows associating topographic sample features of overgrown individual layers to their residual magnetization, as is shown here to be relevant for interpreting the macroscopic AHE data. Although the hump-like features in the AHE suggest a magnetically textured skyrmion phase to exist around 55 K associated with the topological Hall effect (THE), both our MOKE and MFM data cannot support this theory for the ultrathin films investigated. In contrast, our SFM/MFM local-scale analysis finds the local coercive field to be strongly dependent on the effective layer thickness and stoichiometry in both the SRO and RIZ samples, with a huge impact on the local band structure. In fact, it is these variations that in turn mimic a potential THE through anomalies in the AHE resistivity loops. [ABSTRACT FROM AUTHOR]

[Display omitted] • The highest doping level in Bi-hyperdoped Si is achieved via a chip-technology compatible approach. • The epitaxial regrowth of Bi-hyperdoped Si layers and the Bi impurity substitution are confirmed. • In the Bi-hyperdoped Si, a record-high electron-concentration of 1.7 × 1020 cm−3 and a prominent electrical-activation-yield above 50 % are measured. • The magneto-transport behavior in Bi-hyperdoped Si epilayers is tunable by controlling donor concentration, providing a new platform for designing nonmagnetic spin-transport devices. During the past decades, excavating the novel functional materials towards CMOS-compatible spin-transport devices has been treated as one of the most urgent tasks to revolutionize the current Si-based nonmagnetic spintronics. Among various strategies, triggering the exotic physics in Si via utilizing heavy-element hyperdoping is the most straightforward way to achieve the abovementioned expectation. In this work, by using liquid phase epitaxy growth, we have achieved the highest Bi doping level in Si up to 2.0 × 1021 cm−3. The resulting Bi-hyperdoped Si layers are confirmed to be single-crystalline and epitaxially regrown without extended defects or Bi agglomerates via various microstructural analysis. The Bi-hyperdoped Si layers exhibit a metallic-like behavior with the carrier densities up to 1.55 × 1015 cm−2 and a prominent electrical activation yield around 50 %. Negative magnetoresistance due to magnetic-field suppressed weak localization at both sides of the insulator-to-metal transition is observed. Tunable magneto-transport properties are realized in ultra-high Bi doped Si epilayers by controlling the donor concentration. This provides new possibilities for designing Si devices that integrate spin-charge conversion and spin transport. This work promises to enable heavy-element hyperdoped semiconductor epilayers as novel spin-based electronics material platform via a chip-technology compatible approach. [ABSTRACT FROM AUTHOR]

We have studied the diffusion coefficient of hot electrons in GaN crystals under moderate electric (1...10 kV/cm) and magnetic (1...4 T) fields. Two configurations, parallel and crossed fields, have been analyzed. The study was carried out for compensated bulklike GaN samples for various lattice temperatures (30.300 K) and impurity concentrations (1016...1017 cm-3). We found that at low lattice temperatures and low impurity concentrations, electric-field dependences of the transversal-to-current components of the diffusion tensor are non-monotonic for both configurations, while diffusion processes are mainly controlled by the magnetic field. With increasing the lattice temperature or impurity concentration, behaviour of the diffusion tensor becomes more monotonous and less affected by the magnetic field. We showed that this behaviour of the diffusion processes is caused by the distinct kinetics of hot electrons in polar semiconductors with strong electron - optical phonon coupling. We have suggested that measurements of the diffusion coefficient of electrons subjected to electric and magnetic fields facilitate identification of features of different electron transport regimes and development of more efficient devices and practical applications. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Temperature dependent magneto-transport properties of (Cu) x /CuTl-1223 composites were performed. • Improvement in infield superconductivity was observed after inclusion of Cu nanoparticles. • Optimum content level of Cu nanoparticles in (Cu) x /CuTl-1223 composites was found x = 1.0 wt%. • M-H loops indicated mixed superconducting and ferromagnetic behaviour up to 90 K in all samples. Abstract Copper (Cu) nanoparticles and Cu 0.5 Tl 0.5 Ba 2 Ca 2 Cu 3 O 10−δ (CuTl-1223) superconducting phase were synthesized by sol-gel and solid-state reaction, respectively. These metallic Cu nanoparticles were added in CuTl-1223 superconducting matrix to get (Cu) x /CuTl-1223; x = 0–4.0 wt% nanoparticles-superconductor composites and their temperature dependent magneto-transport properties were studied. The zero-field-cooled (ZFC) and field-cooled (FC) temperature dependent magnetization (M-T) measurements of (Cu) x /CuTl-1223 samples showed an increase in transition temperature and in amplitude of diamagnetic signal after the inclusion of Cu nanoparticles in the host CuTl-1223 matrix. The improvement in these magneto-transport properties can be attributed to the increase in number of efficient pinning centres in CuTl-1223 matrix after addition of Cu nanoparticles. Magnetization hysteresis (M-H) loops were obtained at various operating temperatures from which the magnetization critical current density (J c) was estimated using Bean's critical state model. M-H loops indicated the combined superconducting and ferromagnetic behaviour up to 90 K in all (Cu) x /CuTl-1223 samples. Improvement in J c could also be due to increase in number of pinning centres with addition of Cu nanoparticles in CuTl-1223 matrix. Maximum improvement in magneto-transport properties of (Cu) x /CuTl-1223 samples was observed for x = 1.0 wt%, which had specified the optimum content level of Cu nanoparticles in CuTl-1223 phase. [ABSTRACT FROM AUTHOR]

Solid-state reaction method was used to synthesize Cu 0.5 Tl 0 . 5 Ba 2 Ca 2 Cu 3 O 10-δ (CuTl-1223) superconducting phase and sol-gel method was used to prepare cobalt oxide (Co 3 O 4 ) magnetic nanoparticles. These Co 3 O 4 nanoparticles were added in CuTl-1223 superconducting matrix to get (Co 3 O 4 ) x /CuTl-1223; x = 0–2.00 wt.% nanoparticles-superconductor composites. The effects of Co 3 O 4 nanoparticles on crystal structure, phase formation, phase purity and infield superconducting transport properties of CuTl-1223 phase were investigated at different operating temperatures and external applied magnetic fields. The crystal structure and phase formation of Co 3 O 4 nanoparticles and CuTl-1223 superconductor were determined by X-ray diffraction (XRD) technique. XRD peaks of Co 3 O 4 nanoparticles were well indexed according to FCC crystal structure and the average particle size of 70 nm was calculated by using Debye-Scherer's formula. The unaltered crystal structure of host CuTl-1223 superconducting phase (i.e. Tetragonal) with the addition of Co 3 O 4 nanoparticles indicated the dispersion of nanoparticles at inter-granular sites. Temperature dependent magneto-transport superconducting properties of (Co 3 O 4 ) x /CuTl-1223 composites were investigated by zero field cooled (ZFC) and field cooled (FC) magnetic moment versus temperature (M-T) measurements. The onset transition temperatures {T c Onset (K)} was decreased along with the suppression of diamagnetic amplitude of CuTl-1223 superconducting phase with the addition of magnetic Co 3 O 4 nanoparticles. Temperature dependent magnetic hysteresis (M-H loops) measurements of (Co 3 O 4 ) x /CuTl-1223 composites were carried out at different operating temperatures from 5 K to 150 K. Critical current density (J c ) was calculated from M-H loops measurements by using Bean's model. Like the suppression of T c Onset (K) values, J c was also decreased with the inclusion of Co 3 O 4 nanoparticles. It was also observed that variation of J c with H followed the power law J c  = βH −α at low operating temperatures 5 K and 20 K only. [ABSTRACT FROM AUTHOR]

Electrical resistivity, thermoelectric power, magnetotransport and magnetization of Zn doped Bi 2 Te 3 Topological Insulator were studied. Electrical conductivity is enhanced at higher Zn concentration, and the carrier mobility estimated from Hall data reaches a remarkable value of ∼7200 cm 2 V -1 S −1 . Large positive magnetoresistance (MR∼400%) is observed in high mobility samples. Interestingly it is found that the coupling between electrical conductivity and Seebeck coefficient is broken for higher Zn doped Bi 2 Te 3 samples which effectively enhances the thermoelectric power factor (from 2.1mW/K 2 m for Bi 2 Te 3 to 4.64mW/K 2 m for Zn doped Bi 2 Te 3 ). [ABSTRACT FROM AUTHOR]

In this work we have reported the temperature and magnetic field dependence of resistivity and magnetoresistance in electron-doped polycrystalline Ca 0.85 Sm 0.15 MnO 3 (CSMO). It shows a robust semiconducting behavior down to the lowest temperature (5 K) of investigation. High- T resistivity of the present sample follows small polaron hopping (SPH) conduction mechanism. The variable range hopping (VRH) model has been found to fit low- T resistivity data. Intermediate-temperature ρ ( T ) data has been explained using a parallel combination of SPH and 3D-VRH model. The resistivity shows strong dependence on the magnetic field–temperature history. Magnetoresistance (MR) of the sample shows strong irreversibility with respect to sweeping of the field between the highest positive and negative values. Low- ρ state of the envelope curve in MR indicates a manifestation of kinetic arrest of the electronic phase on application of magnetic field. We demonstrates that the sizable MR at low fields dominated by spin-polarized tunneling between the adjacent grains. [ABSTRACT FROM AUTHOR]

The magnetic and magnetotransport properties have been investigated in a family of multilayer glass-coated microwires with a soft CoFeSiB nucleus and magnetically harder Co and CoPtRh deposited outer layers. Their magnetic properties are mainly determined by the magnetic interactions between the magnetic phases, i.e., the magnetoelastic coupling generated by the supplementary mechanical stresses induced by the deposited layers and by the magnetostatic interactions between the soft magnetic inner core and the hard magnetic deposited layers. The deposition of 900 nm-thick hard magnetic layers (Co and CoPtRh) on the soft magnetic CoFeSiB glass-coated microwire leads to a biphase magnetic character. Isothermal annealing at 300 °C for 1 h of multilayer microwires determines a slight decrease of the coercive field, an increase in the relative magnetic permeability, and to an increase in the magnetoimpedance response, more significant for the CoFeSiB/Co multilayer microwires. The possibility to design the magnetic and magnetotransport properties through magnetic coupling and annealing makes these materials very competitive as the functional sensing elements. [ABSTRACT FROM AUTHOR]

The impact of slightly tuning molar ratio in the starting materials on the physical properties of 1212-type rutheno-cuprate, YSrRuCuO (nominal) samples prepared under four synthesis approaches are reported. Interestingly, all samples clearly show the differences in the physical properties of the samples prepared under different synthetic protocols. However, neither XRD nor EDX reveal any notable differences in the crystal structure or sample composition. All the samples exhibit magneto-superconducting properties ( H=5 Oe) which are slightly varied with synthetic approaches. The high field ( H=10 kOe) temperature dependence of magnetization data shows a sharp ferromagnetic transition around 150 K and all the samples obey Curie-Weiss linear behavior above 180 K. The experimental effective paramagnetic moment for the various samples is in the range of 2.5 and 2.7 μ/Ru which are in line with the literature report. The magnetization, M( H) isotherm curves measured at 5 K and −10 kOe≤ H≤10 kOe conditions reveal weak ferromagnetic-like hysteresis loops for all samples with returning moment ( M) and coercive field ( H), whereas the high field M( H) loops indicate soft ferromagnetic behaviors with magnetic saturation. The saturation moment of the samples is slightly varied with the synthesis approaches. None of the samples showed bulk superconductivity ( $T_{\mathrm{c}}^{R = 0})$ down to 2 K, while all samples show onset transitions ( $T_{\mathrm{c}}^{\mathrm{onset}}$) except the sample prepared by approach-3. The latter approach sample shows semiconducting behavior down to 2 K. The $T_{\mathrm{c}}^{\mathrm{onset}}$ noticed at 34 K, 12 K, and 6 K for the sample prepared by approach-1, 2, and 4, respectively. The nearly linear dependence suggests that hopping conduction is dominant in certain temperature range for all samples. The magneto-transport features of these samples exhibit maximum magnetoresistance (MR) at low temperatures. Remarkably, the sample prepared by approach-1 shows largest −MR about 77% at low temperature 2 K and H=90 kOe which stimulates for further investigations. Among the four synthesis approaches employed in the present study, we can probably suggest that the approach-1 (0.5YO+0.5SrO+1.5SrCuO+0.9RuO+0.6CuO) is the preferable method to achieve the best sample ( in terms of magneto-transport features). [ABSTRACT FROM AUTHOR]

Abstract: Magneto-transport measurements have been performed on La0.67Sr0.33Mn1− x Fe x O3 (x =0.0, 0.05 and 0.07) manganites synthesized by solid state route. The overall nature of AC susceptibility is found to be frequency independent. With the substitution of Mn by Fe, the transport properties dramatically change suppressing the double-exchange interaction. This in turn weakens the ferromagnetism and consequently decreases the paramagnetic to ferromagnetic transition temperature (Tc ). However, DC electrical resistivity of the samples show board hump at metal–insulator transition temperature (TMI ) in contrary with sharp transition at Tc and TMI < Tc indicating decoupling of electrical and magnetic properties. Resistivity behavior of these samples can be well explained by the consideration of bond percolation model which is basically developed from effective approximation method. [Copyright &y& Elsevier]

Abstract: Polycrystalline La0.7Ba0.15Sr0.15MnO3 compound shows giant magnetoimpedance (GMI) effect at low field and at low frequency under a temperature range from 300K to its Curie temperature (T C). A sharp change in magnetoimpedance is obtained at low fields up to 1kG, followed by a nearly linear increase at higher field. The frequency dependence of magnetoimpedance becomes prominent near T C only, where as near room temperature; magnetoimpedance shows feeble frequency dependence in MHz region. Present investigation reveals that magnetoimpedance in La0.7Ba0.15Sr0.15MnO3 compound could be exploited as a sensitive tool for room-temperature magnetic field sensing. [Copyright &y& Elsevier]

This article reports the study of the magneto-transport properties of Lanthanum-based colossal magnetoresistive sample, [image omitted], as a function of temperature. The samples were prepared by the solid state route by sintering at three different temperatures 1100°C, 1250°C and 1350°C; with a view to understand the influence of varying crystallite size on various physical properties. It has been observed that the change in the grain size with the sintering temperature alters the contributions of intrinsic and extrinsic resistances which results in some major effects on the magneto-transport behaviours. The occurrence of intrinsic and extrinsic transitions can be explained well by the consideration of the random network of resistances with two types of resistivities - one more resistive than the other; using time dependent and independent metallic volume fractions, respectively. [ABSTRACT FROM AUTHOR]

Abstract: A composite series consisting of colossal magnetoresistive and ferroelectric materials, with chemical formula La0.67Ca0.33MnO3(LCMO)–BaTiO3 (BTO) has been prepared by the solid state route. Influence of BTO phase on structural, magnetic and electric properties of LCMO phase has been investigated. By X-ray diffraction, scanning electron microscopy and Fourier transform of infrared spectroscopy we find that there is no interdiffusion between the LCMO and BTO phases. Susceptibility measurements reveal that the composite samples show paramagnetic to ferromagnetic transition almost at the same Curie temperature (T c) like the parent LCMO sample. Resistivity measurements on these composite samples show more prominent extrinsic metal-insulator (EMI) transition at a temperature T EMI with a small signature of the other peak approximately at the temperature T IMI corresponding to intrinsic M–I transition of the parent LCMO. Investigations on magnetoresistance (MR) using magnetic field upto 3T show two kinds of contribution: one is intrinsic MR and the other is extrinsic MR. [Copyright &y& Elsevier]

Abstract: Two-ordered perovskites, Bi1/3Sr2/3FeO2.67 and Bi1/2Ca1/2FeO2.75, have been stabilized and characterized by transmission electron microscopy, Mössbauer spectroscopy and X-ray powder diffraction techniques. They both exhibit orthorhombic superstructures, one with a≈b≈2a p and c≈3a p (S.G.: Pb2n or Pbmn) for the Sr-based compound and one with a≈b≈2a p and c≈8a p (S.G.: B222, Bmm2, B2mm or Bmmm) for the Ca-based one. The high-resolution transmission electron microscopy (HRTEM) images evidence the existence of one deficient [FeO x ]∞ layer, suggesting that Bi1/3Sr2/3FeO2.67 and Bi1/2Ca1/2FeO2.75 behave differently compared to their Ln-based homolog. The HAADF-STEM images allow to propose a model of cation ordering on the A sites of the perovskite. The Mössbauer analyses confirm the trivalent state of iron and its complex environment with three types of coordination. Both compounds exhibit a high value of resistivity and the inverse molar susceptibility versus temperature curves evidence a magnetic transition at about 730K for the Bi1/3Sr2/3FeO2.67 and a smooth reversible transition between 590 and 650K for Bi1/2Ca1/2FeO2.75. [Copyright &y& Elsevier]

• Single phase polycrystalline Fe 3 Si films were acquired on MgO/Si(1 1 1). • The distribution of scattered particles embedded in films results in rough surface. • The performance of Fe 3 Si films is improved with the increase of atomic ordering. • Anomalous SMS is a unique character of the ferromagnetic Heusler alloy films. • Berry curvature dominates the AHE via a proper scaling law. This work intended to give a comprehensive overview of the atomic ordering dependence of magnetic and magneto-transport properties for polycrystalline Fe 3 Si films on Si(1 1 1) substrates by inserting the MgO buffer layer between them. X-ray diffraction results display that the single phase polycrystalline Fe 3 Si film fulfilling fundamental reflections, B 2 -Fe 3 Si film and D0 3 -Fe 3 Si film are acquired. Scanning electron microscopy images present the distribution of the particles dispersed and embedded in the films, resulting in rough surface. The M s value increases and H c value decreases with the improvement of structural and chemical order. The highly ordered D0 3 -Fe 3 Si film has the highest M s value of 610~657 emu cm−3, and the lowest H c value of 81~93 Oe. Fe 3 Si films characterize metallic behavior and the resistivity declines with the improvement of atomic ordering. The phonon contribution governs the resistivity in the high temperature range and the electron–electron scattering and anomalous single magnon scattering mechanisms are available at the low temperature region of ~30 K~100 K and below ~30 K, respectively. The analysis of anomalous Hall effect demonstrates that Berry curvature dominates the anomalous Hall effect via a proper scaling law. The enhancement of intrinsic anomalous Hall effect contribution is due to the impact of the improvement of structural and chemical order on the band structure/Berry curvature modifications, accordingly affecting the intensity of spin–orbit coupling, whereas the extrinsic contributions behave in opposite manner. [ABSTRACT FROM AUTHOR]

• Pr 0.5 Ca 0.5 Mn 0.9 V 0.1 O 3 crystallizes in O′–type orthorhombic structure and Pnma space group. • The onset of CO at 233 K and spin-glass behavior observed at low temperature regime. • V doping incorporates a field-induced metal–insulator transition with low-temperature Kondo-type behavior. • Large irreversibility in both the M-H and ρ-H plots are observed at low temperature region. • Large values of MR ~ 99.99% and FCR ~ 855% of the sample reveal its important applications. Structural, magnetic and magneto-transport properties of polycrystalline Pr 0.5 Ca 0.5 Mn 0.9 V 0.1 O 3 have been studied. The incorporation of vanadium attributes to enhancement in the Mn3+/Mn4+ ratio as well as density of conducting e g carriers, which affects the magnetic and electrical behavior of the system. On cooling, a multi-phase separated "paramagnetic (PM) – charge-ordered antiferromagnetic (COAFM) – ferromagnetic (FM) – reentrant spin glass (RSG)" phases are observed with the characteristic charge ordering temperature T CO = 233 K and Neel temperature T N = 143 K. Field-induced first-order magnetic phase transition from a charge-ordered antiferromagnetic state to a ferromagnetic cluster glass state takes place at T C = 44 K. A 7 T magnetic field induces metal–insulator transition at T MI = 163 K. At low temperatures, strong memory-effect and colossal magnetoresistance (CMR) ~ 99.99% are observed in resistivity data. The sample shows a high field coefficient of resistance (FCR) value of about 855% in the low-temperature regime. [ABSTRACT FROM AUTHOR]

Abstract: The magnetotransport and magnetostatic properties of synthesized dilute magnetic semiconductors (DMS) In x Mn1− x Sb were studied. The samples with x=0.75–1.33at% Mn manifested the hysteresis at room temperature with the coercive force below 50Oe and the saturation field about 5kOe. Both the magnetoresistance and Hall effect were positive. With the Mn concentration decrease the magnetoresistance significantly increased. The co-doping of these DMS with Zn enhances the ferromagnetic properties according to the kinematic exchange theory. [Copyright &y& Elsevier]

The magneto-transport properties of cubic NiMnAs film epitaxied on the GaAs (110) substrate are investigated. The x-ray diffraction measurements reveal that the NiMnAs (111) crystal plane is parallel to the GaAs (110) crystal plane. The temperature dependence of resistivity at high temperature can be described by a thermal activation model, from which the thermal activation energy is obtained and found to be comparable with many other Heusler alloys. By fitting the temperature dependence of resistivity at low temperature, the coefficient of the quadratic temperature term is determined to be 1.34 × 10 -3 μ . This value suggests the possible presence of single-magnon scattering in the NiMnAs film. The negative magnetoresistance is attributed to the suppression of the spin-dependent scattering, which would not take place in a half-metal. The angle dependence of the anisotropic magnetoresistance (AMR) is measured, and the AMR ratios are positive even at low temperature. These magneto-transport properties indicate that the predicted half-metallicity is destroyed in the NiMnAs film. The absence of the half-metallicity may be attributed to the atomic disorder in the NiMnAs lattice, which needs to be confirmed by further experimental and theoretical studies.-2 . This value suggests the possible presence of single-magnon scattering in the NiMnAs film. The negative magnetoresistance is attributed to the suppression of the spin-dependent scattering, which would not take place in a half-metal. The angle dependence of the anisotropic magnetoresistance (AMR) is measured, and the AMR ratios are positive even at low temperature. These magneto-transport properties indicate that the predicted half-metallicity is destroyed in the NiMnAs film. The absence of the half-metallicity may be attributed to the atomic disorder in the NiMnAs lattice, which needs to be confirmed by further experimental and theoretical studies., (© 2021 IOP Publishing Ltd.)

Using the combination of standard ceramic processing and an infiltration technique, single domain superconductor foam of Y123 has been prepared. In this report we present magneto-transport measurements of these foams. The investigations reveal superconducting properties being similar to those of bulk melt processed materials. The magnetic hysteresis vs field measurements show a high anisotropy of the critical current density up to Jcab/Jcc∼7, in good agreement with the observation of a strong texture as determined from neutron diffraction measurements. [Copyright &y& Elsevier]

This work presents results about the influence of the applied magnetic field on the branching point of the resistive transition in granular samples of the Y1-xPrxBa2Cu3O7-δ (Y123 + Pr) system. Single phase samples of x=0.0 and 0.35 composition were prepared by solid state reaction method. Using several resistance curves as a function of the temperature measured at different applied currents we defined branching points at each magnetic field which was ranged from 0 up to 9 T. We have observed that a line in the H–T phase diagram separates the weak coupling state from decoupled regime of the superconducting clusters. Measurements of current–voltage curves and magneto-resistance hysteresis loops agree with such discussion. [Copyright &y& Elsevier]