We study the relationship between precipitate morphology and superconductivity in KxFe1.6+ySe2 single crystals grown by self-flux method. Scanning electron microscopy (SEM) measurements revealed that the superconducting phase forms a network in the samples quenched above iron vacancy order-disorder transition temperature Ts, whereas it aggregates into micrometer-sized rectangular bars and align...

A non-trivial temperature evolution of superconductivity including a temperature-induced phase transition between two superconducting phases or even a time-reversal symmetry breaking order parameter is in principle expected in multiband superconductors such as iron-pnictides. Here we present scanning tunnelling spectroscopy data of LiFeAs which reveal two distinct superconducting phases: at = 1...

A model incorporating simultaneous superconducting and lattice instabilities has been studied in detail to estimate the nature of coupling and inter-play between them. The phase diagram is obtained in the temperature-filling plane at different values of the parameters of the model. It is found that a pseudogap develops in the distorted phase that inhibits the appearance of the superconducting t...

The new class of phenomena described in this review is based on the interaction between spatially separated, but closely located ferromagnets and superconductors, the so-called ferromagnet–superconductor hybrids (FSH). Typical FSH are: coupled uniform and textured ferromagnetic and superconducting films, magnetic dots over a superconducting film, magnetic nanowires in a superconducting matrix, ...

We report measurements of the pressure dependence of the low-temperature magnetization that show that the two pressure induced magnetic transitions in UGe2 are of first order. Further, the pressure dependence of the uniform susceptibility relative to the superconducting transition is not as expected if the latter is driven by the proximity to a ferromagnetic quantum critical point. Our data ins...

In this study, as much as 10 and 15 wt.% nanosized silicon and carbon (Si+C) were reacted with (Mg+2B) at 650°C and 850°C, respectively, for 1 hour. The phase formation, surface morphology and superconducting properties of these samples were evaluated. The relative peak intensity as calculated from the XRD patterns indicates the formation of large Mg2Si volume fraction at low sintering temperat...

The influence of a Zeeman magnetic field on the superconducting characteristics of the attractive Hubbard model has been investigated. The ground state and temperature phase diagrams have been obtained for a fixed number of particles. Two critical magnetic fields have been found for the first order phase transition from the superconducting (SC) to the normal (NO) state for n 6= 1. For some rang...

Stimulated by the discovery of high-temperature superconductivity, the electronic structure of late 3d transition-metal oxides is presently one of the most extensively studied subjects in condensed matter physics. In this review, we hope to summarize the progress we have made and the problems we are facing. The emphasis of the review is on the latest angle-resolved photoemission studies that ha...

Citation Ivry, Yachin, et al. "Universal scaling of the critical temperature for thin films near the superconducting-to-insulating transition." The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters.

We report In nuclear magnetic resonance (NMR) measurements in the heavy-fermion superconductor CeCoIn5 as a function of temperature in different magnetic fields applied parallel to the (â, b̂) plane. The measurements probe a part of the phase diagram in the vicinity of the superconducting critical field Hc2 where a possible inhomogeneous superconducting state, Fulde-Ferrel-LarkinOvchinnikov (FFL...