Because the valleys in the band structure of graphene are related by time-reversal symmetry, electrons from one valley are reflected as holes from the other valley at the junction with a superconductor. We show how this Andreev reflection can be used to detect the valley polarization of edge states produced by a magnetic field. In the absence of intervalley relaxation, the conductance GNS=(2e2/...

To synthesize a new superconductor which has a critical temperature, Tc, exceeding the room temperature, one needs to know what chemical components to start with. This chapter presents analysis of experimental data which allow one to draw a conclusion about components and the structure of a potential room-temperature superconductor. The two essential components of a roomtemperature superconduct...

A hybrid system, consisting of an array of Fe nanodots covered by a superconducting Al thin film, exhibits very unusual magnetotransport, including a giant hysteretic magnetoresistance with different reversible or irreversible regimes related to the magnetic state of the array. These effects originate from the magnetic fields produced by magnetic nanodots in the "magnetic vortex state." This is...

Contrary to recent theoretical prediction, we show that the magnetic flux of a vortex in SU(2) model of two-gap superconductor is quantized in units of 2π/g, not 4π/g. For the U(1) version of this model, the flux is quantized in units of 2πα/g where 0 < α < 1. The parameter α depends on the masses and concentrations of the Cooper pairs in the two condensates. PACS number(s): 74.20.De, 74.25.Qt,...

Article history: Received 12 July 2017 Received in revised form 9 October 2017 Accepted 17 October 2017 Available online xxxx Superconductor-Ferromagnet (SF) heterostructures are of interest due to numerous phenomena related to the spin-dependent interaction of Cooper pairs with the magnetization. Here we address the effects of a magnetic insulator on the density of states of a superconductor b...

A magnetic atom inside a superconductor locally distorts superconductivity. It scatters Cooper pairs as a potential with broken time-reversal symmetry, leading to localized bound states with subgap excitation energies, named Shiba states. Most conventional approaches regarding Shiba states treat magnetic impurities as point scatterers with isotropic exchange interaction. Here, we show that the ...

We study the finite temperature electroweak phase transition in an external hypercharge U(1) magnetic field HY , using lattice Monte Carlo simulations. For sufficiently small fields, HY /T 2 <∼ 0.3, the magnetic field makes the first order transition stronger, but it still turns into a crossover for Higgs massesmH <∼ 80 GeV. For larger fields, we observe a mixed phase analogous to a type I supe...

Andreev reflection in ferromagnet-superconductor junctions is derived in a regime in which Zeeman splitting dominates the response of the superconductor to an applied magnetic field. Spin-up and spin-down Andreev reflections are shown to be resolved as voltage is increased. In the metallic limit, the transition from Andreev to tunnel conductivity in the spin-up channels has a non trivial behavi...

Through the analytic solutions of the Bogoliubov de Gennes (BdG) equations the effect of a static and homogeneous magnetic field applied parallel to the interface of an NIS (N: Normal metal, S: superconductor and I: Insulator) junction on the differential conductance is calculated. For a dxy symmetry we obtain zero bias conductance peak that can be split by a magnetic field. The shift of the ze...

Abstract. We carry out a systematic analytic investigation of stationary and cylindrically symmetric vortex configurations for simple models representing an incompressible non-relativistic superconductor in a background, which is rigidly rotating with the angular velocity Ω∞. It is shown that although the magnetic and kinetic contributions to the energy per unit length of such a vortex are sepa...