Iver Bakken Sperstad

Josephson current in diffusive multilayer superconductor/ferromagnet/superconductor junctions

We calculate the Josephson current in a diffusive superconductor/ferromagnet/superconductor junction, where the ferromagnetic region contains multiple layers (or domains). In particular, we study a configuration where there are two layers with an arbitrary relative in-plane magnetization orientation and also include nonideal interfaces and arbitrary spin-flip scattering. We study the

Coexistence of itinerant ferromagnetism and a non-unitary superconducting state with line nodes : Possible application to UGe2

0\text{\ensuremath{-}}\ensuremath{\pi}

Three distinct types of quantum phase transitions in a (2+1)-dimensional array of dissipative Josephson junctions

oscillations of the critical current for varying junction width

Quantum criticality in spin chains with non-Ohmic dissipation

d

Quantum criticality in a dissipative (2+1)-dimensional

and find that the

XY

\ensuremath{\pi}

model of circulating currents in high-

state vanishes entirely when the magnetic misorientation angle of the two layers exceeds a critical angle

T_{\rm c}

{\ensuremath{\phi}}_{c}

cuprates

. While

Monte Carlo simulations of dissipative quantum Ising models

{\ensuremath{\phi}}_{c}\ensuremath{\rightarrow}\ensuremath{\pi}/2