– We investigate one dimensional models (the Blonder, Tinkham, Klapwijk model and a tight-binding model) of non local transport at normal metal / superconductor (NS) double interfaces. We find a negative elastic cotunneling crossed conductance, strongly enhanced by additional scatterers away from the interfaces, suggesting the possibility of reflectionless tunneling non local transport at doubl...

Topological superconductivity in one dimension requires time-reversal symmetry breaking, but at the same time, it is hindered by external magnetic fields. We offer a general prescription for inducing topological planar superconductor-normal-superconductor-normal-superconductor (SNSNS) Josephson junctions without applying any fields on junctions. Our platform relies two key ingredients: three pa...

Since the discovery of high transition-temperature (high Tc ) superconductivity in layered copper oxides [1], they have held the pole position in the race for achieving higher Tc [2]. In this race many different compounds which contain copper oxide layers has been examined. Although there are reports of Tc s up to 185K for very rare phases of complex compounds like (Sn1.0Pb0.5In0.5)Ba4Tm5Cu7O20...

We review what is different and what is similar in a color superconductor as compared to an ordinary BCS superconductor. The parametric dependence of the zero-temperature gap, φ0, on the coupling constant differs in QCD from that in BCS theory. On the other hand, the transition temperature to the superconducting phase, Tc, is related to the zero-temperature gap in the same way in QCD as in BCS ...

We calculate the local density of states (LDOS) of a superconductor-normal metal sandwich at arbitrary impurity concentration. The presence of the superconductor induces a gap in the normal metal spectrum that is proportional to the inverse of the elastic mean free path l for rather clean systems. For a mean free path much shorter than the thickness of the normal metal, we find a gap size propo...

FRG The subgap conductivity of a normal-superconductor (NS) tunnel junction is thought to be due to tunneling of two electrons. There is a strong interference between these two electrons, originating from the spatial phase coherence in the normal metal at a mesoscopic length scale and the intrinsic coherence of the superconductor. We evaluated the interference effect on the transport through an...

We study the normal state conductance and the Josephson current in a superconductor-2DEG-superconductor structure where the size/shape of the 2DEG-region can be modified by an additional side-gate electrode. The considered transport properties follow from the retarded Green function which we compute by employing a tight-binding-like representation of the Hamiltonian in the 2DEG region. Our mode...