Under special conditions, a superconducting state where the order parameter oscillates in real space, the so-called FFLO state, is theoretically predicted to exist near the upper critical field, as first proposed by Fulde and Ferrell, and Larkin and Ovchinnikov. We report systematic measurements of the interlayer resistance in high magnetic fields to 45 T in the two-dimensional magnetic-field-induced organic superconductor lambda-(BETS)2FeCl4, where BETS is bis(ethylenedithio)tetraselenafulvalene. The resistance is found to show characteristic dip structures in the superconducting state. The results are consistent with pinning interactions between the vortices penetrating the insulating layers and the order parameter of the FFLO state. This gives strong evidence for an oscillating order parameter in real space.
Current flow through Pt/(Ba0.7Sr0.3)TiO3/Pt stack consists of both polarization current and electronic leakage current, which were separated by monitoring the discharging current when applied voltage was turned off. Electronic current comes from electrical field enhanced Schottky emission at the electrode–dielectric interface, and dominates the current flow at high electric field. At low electric field, polarization current prevails. The voltage and time dependence of the polarization current can be modeled by a distribution of Debye-type relaxations. The relaxation time and capacitance derived from current–time measurements were applied to simulate the current–voltage behavior, where good fitting to experimental result was obtained.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.