Related papers: Superconductivity in Ultrasmall Metallic Grains
Recent experiment on the tunneling spectra of ultrasmall superconducting grains revealed an unusual structure of the lowest differential conductance peak for grains in the odd charging states. We explain this behavior by nonequilibrium…
We present a quantum transport theory for generic magnetic metals, in which magnetism occurs predominantly due to exchange interactions, such as ferromagnets, antiferromagnets, altermagnets and p-wave magnets. Our theory is valid both for…
Scanning tunneling spectroscopies are performed below 100~mK on nano-crystalline boron-doped diamond films characterized by Transmission Electron Microscopy and transport measurements. We demonstrate a strong correlation between the local…
We study pairing correlations in ultrasmall superconductor in the nanoscopic limit by means of a toy model where electrons are confined in a single, multiply degenerate energy level. We solve the model exactly to investigate the temperature…
It is shown that a non-magnetic metallic band in the presence of an antiferromagnetic background coupled only by the exchange interaction develops a superconducting instability similar to the one described by BCS theory plus additional…
We propose a simple phenomenological model for an ultrasmall ferromagnetic grain, formulated in terms of the grain's discrete energy levels. We compare the model's predictions with recent measurements of the discrete tunneling spectrum…
We calculate the effect of scattering on the static, exchange enhanced, spin susceptibility and show that in particular spin orbit scattering leads to a reduction of the giant moments and spin glass freezing temperature due to dilute…
Within a simple model Hamiltonian, both superconductivity and metallic ferromagnetism can be understood as arising from lowering of kinetic energy as the ordered state develops, due to a reduction in the carriers effective mass, or…
We study the fluctuation conductivity of superconducting granular metals at low temperatures and strong magnetic field destroying the Cooper pairs. Explicit calculations are performed for larger values of the coupling between the grains…
We study the spin susceptibility chi of a small, isolated superconducting grain. Due to the interplay between parity effects and pairing correlations, the dependence of chi on temperature T is qualitatively different from the standard BCS…
In contrast to conventional s-wave superconductivity, unconventional (e.g. p or d-wave) superconductivity is strongly suppressed even by relatively weak disorder. Upon approaching the superconductor-metal transition, the order parameter…
A variety of experimental observations in monolayer transition metal dichalcogenide superconductors with Ising spin-orbit coupling suggest the presence of an unconventional superconducting pairing mechanism. Some of these experiments…
Atomic nuclei and nano-scale metallic grains are in the crossover regime of pairing correlations between the bulk limit, where the Bardeen-Cooper-Schrieffer (BCS) theory of superconductivity is valid, and the fluctuation-dominated regime,…
This Chapter gives a brief introduction to some basic aspects metals and superconductors in crystal without inversion symmetry. In a first part we analyze some normal state properties which arise through antisymmetric spin-orbit coupling…
We have observed a superparamagnetic to ferromagnetic transition in films of isolated Ni grains covered by non-magnetic overlayers. The magnetoresistance (MR) of the films was measured as a function of the overlayer thickness. Initially,…
The theoretical description and the survey of physical properties of superconducting states in the uranium ferromagnetic materials are presented. On the basis of microscopic theory is shown that the coupling between the electrons in these…
On the basis of microscopic theory it is demonstrated how the coupling between the electrons by means of magnetization fluctuations in ferromagnetic metal with orthorhombic symmetry gives rise equal spin pairing superconducting state with…
Recent experimental advances in surface science have made it possible to track the evolution of superconductivity in films as the thickness enters the nanoscale region where it is expected that the substrate plays an important role. Here,…
We consider effects of an externally applied electrostatic field on superconductivity, self-consistently within a BCS mean field model, for a clean 3D metal thin film. The electrostatic change in superconducting condensation energy scales…
The planar-diagrammatic technique of large-$N$ random matrices is extended to evaluate averages over the circular ensemble of unitary matrices. It is then applied to study transport through a disordered metallic ``grain'', attached through…