Electron reflection at an interface is a fundamental quantum transport phenomenon. The most famous electron reflection is the electron→hole Andreev reflection (AR) at a metal/superconductor interface. While AR can be either specular or retro-type, electron→electron reflection is limited to only the specular type. Here we show that electrons can undergo retro-reflection in bilayer graphene (BLG)...

Submitted for the MAR10 Meeting of The American Physical Society Nonequilibrium dynamics of weakly and strongly paired superconductors1 VICTOR GURARIE, University of Colorado — We study small oscillations of the order parameter in weakly and strongly paired superconductors driven slightly out of equilibrium, in the collisionless approximation. While it was known for quite some time that the amp...

We obtain an effective string theory of the Abrikosov–Nielsen–Olesen vortices of the Abelian Higgs model. The theory has an anomaly free effective string action which, when expanded in powers of the extrinsic curvature, yields the Nambu–Goto action and a rigidity term which is negative. This generalizes previous work in which a string representation was obtained in the London limit where the ma...

For any practical superconductor the magnitude of the critical current density, Jc, is crucially important. It sets the upper limit for current in the conductor. Usually Jc falls rapidly with increasing external magnetic field, but even in zero external field the current flowing in the conductor generates a self-field that limits Jc. Here we show for thin films of thickness less than the London...

Although Brownian ratchets have been conceived to describe the operation of molecular motor proteins, their basic principles are also applicable to a wide range of different physical systems. In this paper I line up two such possible applications in condensed-matter physics. The first one is the removal of vortices from superconductors. Magnetic fields frequently penetrate superconducting mater...

Resonant proximity effect in the normal metal/insulator/diffusive ferromagnet/insulator/swave and d-wave superconductor N/I/DF/I/S junctions is studied for various regimes by solving the Usadel equation with the generalized boundary conditions. Conductance of the junction and the density of states in the DF layer are calculated as a function of the insulating barrier heights at the interfaces, ...

We report remarkable photovoltaic effect in YBa2Cu3O6.96 (YBCO) ceramic between 50 and 300 K induced by blue-laser illumination, which is directly related to the superconductivity of YBCO and the YBCO-metallic electrode interface. There is a polarity reversal for the open circuit voltage Voc and short circuit current Isc when YBCO undergoes a transition from superconducting to resistive state. ...

– We consider ferromagnetic particles embedded into a superconductor and study the screening of their magnetic moments by the spins of the Cooper pairs in the superconductor. It is shown that a magnetic moment opposite to the one of the ferromagnetic particle is induced in the superconductor. In the case of a small itinerant ferromagnet grain and low temperatures the full screening of the magne...

S u m m a r y . T h e conditions for the existence of non-perturbative type ~ superconductor ~) solutions of field theories are examined. A non-covariant canonical transformation method is used to find such solutions for a theory of a fermion interacting with a pseudoscalar bosom A covariant renormalisable method using Feynman integrals is then given. A (~ superconductor ~) solution is found wh...