Related papers: Type II superconductivity in SrPd2Ge2
The heavy fermion superconductor URu$_2$Si$_2$ is a candidate for chiral, time-reversal symmetry-breaking superconductivity with a nodal gap structure. Here, we microscopically visualized superconductivity and spatially inhomogeneous…
Searching for functional square lattices in layered superconductor systems offers an explicit clue to modify the electron behavior and find exotic properties. The trigonal SnAs3 structural units in SnAs-based systems are relatively…
We develop a description of the mixed state of type II superconductivity valid within a wide range of temperatures and external magnetic fields. It is based on the quasiclassical version of microscopic BCS theory and employs an expansion in…
We have investigated a gap structure in a newly-discovered superconductor, MgB2 through the measurement of 11B nuclear spin-lattice relaxation rate, ^{11}(1/T_1). ^{11}(1/T_1) is proportional to the temperature (T) in the normal state, and…
We calculate the microwave conductivity of a two band superconductor with $s^\pm$ gap symmetry. Inelastic scattering is included approximately in a BCS model augmented by a temperature dependent quasiparticle scattering rate assumed,…
We have observed superconductivity in heavy p-doped Ge by measuring of differential resistance dV/dI(V) of Ge - PtIr point contacts. The superconducting (SC) features disappear above 6 K or above 1 T, what can be taken as the critical…
Recent intensive experimental studies revealed that (Y,Lu)Ni$_2$B$_2$C is an anisotropic s-wave superconductor. In addition, its gap function possesses deep point minima, whose ratio of the gap anisotropy is more than 10. On the theoretical…
We compute the structure of flux $h/(2e)$ vortices in a d-wave superconductor which emerges from a higher temperature pseudogap metal. Such a transition is described by a continuum theory of the Higgs condensation of 2 flavors of charge $e$…
In the iron pnictide superconductors, two distinct unconventional mechanisms of superconductivity have been put forth: One is mediated by spin fluctuations leading to the s+- state with sign change of superconducting gap between the hole…
In many cases, unconventional superconductivity are realized by suppressing another order parameter, such as charge density wave (CDW) or spin density wave (SDW). This suggests that the fluctuations of these order parameters play an…
We present a broadband optical-conductivity study of superconducting single-crystalline EuFe2(As1-xPx)2 with three different substitutional levels. We analyze the normal-state electrodynamics by decomposing the conductivity spectra using a…
Superconductors with a van der Waals (vdW) structure have attracted a considerable interest because of the possibility for truly two-dimensional (2D) superconducting systems. We recently reported NaSn2As2 as a novel vdW-type superconductor…
Superconductivity in alkali-intercalated iron selenide, with T_c's of 30K and above, may have a different origin than that of the other Fe-based superconductors, since it appears that the Fermi surface does not have any holelike sheets…
The thermal conductivity of iron-based superconductor CsFe$_2$As$_2$ single crystal ($T_c =$ 1.81 K) was measured down to 50 mK. A significant residual linear term $\kappa_0/T$ = 1.27 mW K$^{-2}$ cm$^{-1}$ is observed in zero magnetic…
We report calculations of the electronic structure and magnetic properties of YFe$_2$Ge$_2$ and discuss the results in terms of the observed superconductivity near magnetism. We find that YFe$_2$Ge$_2$ is a material near a magnetic quantum…
Spin-flip scattering from magnetic impurities has a strong pair-breaking effect in $s$-wave superconductors where increasing the concentration of impurities rapidly destroys superconductivity. For small Kondo temperature $T_K$ the…
The recent suggestion of valence-skipping phenomenon driving a two-gap superconductivity in $Ag$-doped SnSe, by Kataria, \textit{et al.} [Phys. Rev. B 107, 174517 (2023)], has brought to the fore a long-standing issue once again. The…
The interplay between spin-orbit interaction (SOI) and magnetism produces interesting phenomena in superconductors. When a two-dimensional (2D) system with strong SOI is coupled to an $s$-wave superconductor, an in-plane magnetic field can…
${\rm CaPd_2Ge_2}$ which crystallizes in ${\rm ThCr_2Si_2}$-type body-centered tetragonal structure exhibits superconductivity below the critical temperature $T_{\rm c} = 1.69$~K\@. We have investigated the superconducting gap structure and…
We derive the exact modified London equation for the two-gap superconductor, compare it with its single-gap counterpart. We show that the vortices in the two-gap superconductor are soft (or continuous) core vortices. In particular, we…