We describe a new technique for the synthesis of ultrahomogeneous nanoparticles of precursor oxalate powder by coprecipitation in the aqueous core of a water-in-oil microemulsion for the preparation of Bi-Pb-Sr-Ca-Cu-0 (2223) oxide superconductor. This process ensures a uniform mixing of metal cations down to a scale of at least 10 nm. This finely dispersed precursor powder results in phase pur...

Recent neutron scattering, nuclear magnetic resonance, and scanning tunneling microscopy experiments have yielded valuable new information on the interplay between charge and spin density wave order and superconductivity in the cuprate superconductors, by using an applied perpendicular magnetic field to tune the ground state properties. We compare the results of these experiments with the predi...

20 IMR KINKEN Research Highlights 2009 Future Energy / Environmental Materials By systematic crystal structure refinements of characteristic superconductor, FeSe1-xTex (x= 0.5, 0.625, 0.75, 0.875) and FeSe by the powder neutron diffraction technique, we studied the relationship between crystal structre and superconductivity. In this work, we found the role of Fe-X network (X; calcogens, pnictog...

We study the dynamics of normal domains in a multifilamentary composite superconductor with a large amount of stabilizer outside the multifilamentary area. We consider the case when there is a transition layer with high thermal and electrical resistance between the superconductor and the stabilizer. We show the existence of localized and propagating normal domains in these composites. We derive...

We analyze the chiral p-wave superconductor in the low temperature region. The superconductor has a εxpx + iεypy-wave gap in two dimensional space (2D). Near the second superconducting transition point, the system could be described by a quasi-1D chiral p-wave model in 2D. The axial anomaly occurs in such a model and causes an accumulation of the quasiparticle in an inhomogeneous magnetic field...

We present detailed thermodynamic and transport measurements on single crystals of the recently discovered binary intermetallic superconductor, SrSn(4). We find this material to be a slightly anisotropic three-dimensional, strongly coupled, possibly multiband, superconductor. Hydrostatic pressure causes a decrease in the superconducting transition temperature at the rate of ≈ - 0.068 K kbar(-1)...

High transmissivity, ferromagnet-superconductor thin film nanocontacts are studied experimentally. Compared to nonmagnetic metal-superconductor contacts, Andreev reflection is strongly suppressed due to the spin polarization of conduction electrons in the ferromagnet. This effect is used to measure both the transparency of the interface and spin polarization of the direct current in the ferroma...

We investigate the crossed Andreev reflections between two graphene leads connected by a narrow superconductor. When the leads are, respectively, of the n and p type, we find that electron elastic cotunneling and local Andreev reflection are both eliminated even in the absence of any valley-isospin or spin polarizations. We further predict oscillations of both diagonal and cross conductances as...

We describe current-voltage measurements on superconducting Nb/lnGaAs junction field-effect transistors which reveal a crossover from tunneling-dominated to Andreev scattering-dominated transport at the superconductor-semiconductor contacts as Schottky barrier thickness decreases with increasing interfacial dopant concentration. These measurements are the first demonstration of such a crossover...

A proximity-effect thermometer measures the temperature dependent critical supercurrent in a long superconductor normal metal superconductor (SNS) Josephson junction. Typically, the transition from the superconducting to the normal state is detected by monitoring the appearance of a voltage across the junction. We describe a new approach to detect the transition based on the temperature increas...