The BCS energy gap at low density

A mixed mean - field / BCS phase with an energy gap at high T c

A mixed mean-field/BCS phase with an energy gap at high T c Abstract We construct a pair potential which in a scaling limit leads to a Hamiltonian that generates co-existing mean-field and superconducting phases. Depending on the relative values of the coupling constants, the superconducting phase may exist at arbitrarily high temperatures. ⋆ Work supported in part by " Fonds zur Förderung der ...

LOW-ENERGY-ION ENHANCED DIFFUSION AT THE SURFACE OF METALS

Radiation enhanced diffusion at the surface of metals has been observed and studied for low-energy nitrogen ions at the surface of copper. The displacement of the target atoms during irradiation creates vacancies and other defects near the surface, thus enhancing the diffusion of implanted materials toward the surface and also into the solid. The mechanism has been studied here by a specia...

Perturbed bifurcations in the BCS gap equation.

The BCS - like gap in superconductor

Since the discovery of superconductivity in the cuprates two decades ago, it has been firmly established that the CuO 2 plane is consequential for high T C superconductivity and a host of other very unusual properties. A new family of superconductors with the general composition of LaFeAs(O 1-x F x) has recently been discovered 1-8 but with the conspicuous lacking of the CuO 2 planes, thus rais...

A BCS Gap on the Lattice

Monte Carlo simulations of the 3+1 dimensional NJL model are performed with baryon chemical potential μ > 0. For μ ∼ Σ0, the constituent quark mass in vacuum, chiral symmetry is restored and a diquark condensate 〈qq+〉 forms. We analyse the fermion propagator and find evidence for particle-hole mixing in the vicinity of the Fermi surface and an energy gap ∆ > 0, both of which provide evidence fo...