相关论文: Impurity scattering in superconductors
Multi-band superconductivity is realized in a plethora of systems, from high-temperature superconductors to very diluted superconductors. While several properties of multi-band superconductors can be understood as straightforward…
We study theoretically orbital effects of a parallel magnetic field applied to a disordered superconducting film. We find that the field reduces the phase stiffness and leads to strong quantum phase fluctuations driving the system into an…
The current dependence of the excess conductivity is measured up to $\simeq 3 T_c$ for a Bi$_2$Sr$_2$CuO$_{6+\delta}$ thin film, as a function of doping. It is found to be anomalously sensitive to the transport current and to behave as a…
Suppression of the critical temperature in homogeneously disordered superconducting films is a consequence of the disorder-induced enhancement of Coulomb repulsion. We demonstrate that for the majority of thin films studied now this effect…
It is well known that external magnetic fields and magnetic moments of impurities both suppress superconductivity. Here, we demonstrate that their combined effect enhances the superconductivity of a few atomic layer thick Pb films grown on…
Weak impurity scattering produces a narrow band with a finite density of states near the phase difference $\phi =\pi$ in the mid-gap energy spectrum of a macroscopic superconducting weak link. The equivalent distribution of transmission…
We present a theory of combined nonmagnetic and magnetic impurity scattering in anisotropic superconductors accounting for the momentum-dependent impurity potential. Applying the model to the d-wave superconducting state, we obtain a…
The $s_\pm$ and $s_{++}$ models for the superconducting state are subject of intense studies regarding Fe-based superconductors. Depending on the parameters, disorder may leave intact or suppress $T_c$ in these models. Here we study the…
We will summarize here some of our measurements of the superconducting fluctuations effects on the in-plane electrical resistivity (the so-called in-plane paraconductivity) in La_{2-x}Sr_xCuO_4 thin films with different Sr content. Our…
The ubiquitous temperature ($T$)-linear behaviour of the transport scattering rate in the normal state of strongly correlated electron systems is called strange metallicity…
The influence of the impurity on the resonant Andreev reflection through a normal-metal/carbon-nanotube/superconductor system is studied theoretically. It is found that the resonant Andreev reflection depends on the strength of the impurity…
In conventional superconductors, magnetic impurities form an impurity band due to quantum interference of the impurity bound states, leading to suppression of the superconducting transition temperature. Such quantum interference effects can…
We report measurements of the four terminal temperature dependent resistance of narrow Au wires implanted with ~100 ppm Fe impurities in proximity to superconducting Al films. The wires show an initial decrease in resistance as the…
Impurity-induced quasiparticle bound states on a pair-breaking surface of a d-wave superconductor are theoretically described, taking into account hybridization of impurity- and surface-induced Andreev states. Further a theory for effects…
Optical conductivity of a moderately disordered superconducting NbN film was investigated by terahertz time-domain spectroscopy in external magnetic field applied along the film plane. The film thickness of about 5 nm was comparable with…
We report theoretical and experimental studies of the effect of Zn-impurity in Fe-based superconductors. Zn-impurity is expected to severely suppress sign reversed s$_\pm$ wave pairing. The experimentally observed suppression of T$_c$ under…
By considering the Ginzburg-Landau model, compactified in one of the spatial dimensions, and using a modified Matsubara formalism, we determine the dependence of the superconducting transition temperature (T_c) of a film as a function of…
We analyze how the magnetic disorder affects the properties of the two-band $s_\pm$ and $s_{++}$ models, which are subject of hot discussions regarding iron-based superconductors and other multiband systems like MgB$_2$. We show that there…
Doping of semiconductors by impurity atoms enabled their widespread technological application in micro and opto-electronics. For colloidal semiconductor nanocrystals, an emerging family of materials where size, composition and shape-control…
Porous silicon, obtained by electrochemical etching, has been used as a substrate for the growth of nanoperforated Nb thin films. The films, deposited by UHV magnetron sputtering on the porous Si substrates, inherited their structure made…