相关论文: Extremely Small Energy Gap in the Quasi-One-Dimens…
In this article we review essential natures of superconductivity in strongly correlated electron systems (SCES) from a universal point of view. After summarizing experimental results on typical materials such as high-$T_{\rm c}$ cuprates,…
We use a diagrammatic approach to study low energy physics of a two dimensional electron system where the Fermi level is near van-Hove singularies in the energy spectrum. We find that in most regions of the $\epsilon_F-T$ phase diagram the…
Bulk superconductivity in a topological semimetal is a first step towards realizing topological superconductors, which can host Majorana fermions allowing us to achieve quantum computing. Here, we report superconductivity and compensation…
A discrete charge transfer in a small tunnel junction where Coulomb interactions are important can excite electron-hole pairs near the Fermi level. We use a simple model to study the associated nonequilibrium properties and found two novel…
Despite the intense theoretical and experimental effort, an understanding of the superconducting pairing mechanism of the high-temperature superconductors is still lacking. An additional puzzle is the unknown connection between the…
The unique electronic structure found at interfaces between materials can allow unconventional quantum states to emerge. Here we observe superconductivity in electron gases formed at interfaces between (111) oriented KTaO$_3$ and insulating…
Optical spectroscopy was used to study the electrodynamics and hidden transport properties of a BaFe$_{1.91}$Ni$_{0.09}$As$_{2}$ thin superconducting film. We analyzed the normal state data using a Drude-Lorentz model with two Drude…
Andreev reflection spectra have been measured in a new superconductor EuAsFeO0.85F0.15 having an unexpectedly low superconducting transition temperature Tc~11.3 K among related FeAs compounds on a base Sm and Gd surrounding Eu in the series…
We analyze the anomalies of superconducting state within a simple exactly solvable model of the pseudogap state, induced by fluctuations of ``dielectric'' short range order, for the model of the Fermi surface with ``hot'' patches. The…
The phase diagrams of quasi two-dimensional organic superconductors display a plethora of fundamental phenomena associated with strong electron correlations, such as unconventional superconductivity, metal-insulator transitions, frustrated…
The interplay between superconductivity and the pseudogap is an important aspect of cuprate physics. However, the nature of the pseudogap remains controversial, in part because different experiments have suggested different gap functions.…
The spontaneous rotational symmetry breaking (RSB), a hallmark phenomenon in cuprate and iron-based high-temperature superconductors, is believed to intimately connected to superconductivity, both of which originate from interactions among…
We derive a so-called gap equation for superconductivity in a quasi-one-dimensional (Q1D) layered conductor in a magnetic field, which is parallel to both its conducting plane and its conducting axis. This equation demonstrates that the…
We have studied the electronic structure of two Chevrel-phase compounds, Mo$_6$Se$_{7.5}$ and Sn$_{1.2}$Mo$_6$Se$_{7.5}$, by combining photoemission spectroscopy and band-structure calculations. Core-level spectra taken with x-ray…
Recent scanning tunneling microscopy measurements on cuprate superconductors have revealed remarkable spatial inhomogeneities in the single-particle energy gap. Using cellular dynamical mean-field theory, we study the zero temperature…
Polarized electronic Raman scattering from the NCCO superconductor at optimal electron doping (T_c=22 K) reveals the formation of an anisotropic pseudogap below a characteristic temperature T* ~ 220 K and energy E*_g = 850 cm-1. Below T* a…
A central mystery in high-temperature cuprate superconductors is the coexistence of multiple exotic orders, which is presumably associated with strong electronic correlation. The ongoing interest in this enigmatic phenomenon is further…
The large single crystals of SrSnP were prepared using Sn self-flux method. The superconductivity in the tetragonal SrSnP is observed with the critical temperature of ~2.3 K. The results of a crystallographic analysis, superconducting…
We present scanning tunnelling spectroscopy measurements on the heavy fermion superconductor PrOs$_4$Sb$_{12}$. Our results show that the superconducting gap opens over a large part of the Fermi surface. The deviations from isotropic BCS…
We present the results of measurements of the thermal and electrical conductivity in the basal plane of single-crystalline MgB_2 between 2 and 300 K. The analysis of the temperature dependence of the thermal conductivity gives supporting…