Related papers: Interstitial anionic electrons involved supercondu…
Superconductors based on transition metal dichalcogenides are of substantial current relevance, towards attaining topological superconductivity. Here we report a detailed study on the synthesis and electromagnetic characterization of…
LiFeAs is unique among the broad family of FeAs-based superconductors, because it is superconducting with a rather large $T_c\simeq 18$ K under ambient conditions although it is a stoichiometric compound. We studied the electrical transport…
We have measured the reflectivity spectra of the iron based superconductor LiFeAs (Tc = 17.6 K) in the temperature range from 4 to 300 K. In the superconducting state (T < Tc), the clear opening of the optical absorption gap was observed…
Superconductivity has been first observed in TlNi$_2$Se$_2$ at T$_C$=3.7 K and appears to involve heavy electrons with an effective mass $m^*$=14$\sim$20 $m_b$, as inferred from the normal state electronic specific heat and the upper…
Thermal conductivity and specific heat were measured in the superconducting state of the heavy fermion material Ce_{1-x}La_{x}CoIn_{5}. With increasing impurity concentration x, the suppression of T_{c} is accompanied by the increase in the…
The crystal structure and numerous normal and superconducting state properties of layered tetragonal (P4/nmm) LaFeAsO, with F-doping of 11 %, are reported. Resistivity measurements give an onset transition temperature Tc = 28.2 K, and low…
Superconductivity with transition temperature Tc above 40 K was observed in protonated FeSe (Hy-FeSe) previously with the ionic liquid of EMIM-BF4 used in the electrochemical process. However, the real superconducting phase is not clear…
The recently discovered spin-triplet superconductor candidate UTe2 with Tc = 2 K has attracted enormous attention because it possesses many interesting properties, such as the extremely high upper critical field Hc2(0), chiral…
We report intrinsic ferromagnetism in monolayer electrides or electrenes, in which excess electrons act as anions. Our first-principles calculations demonstrate that magnetism in such electron-rich two-dimensional (2D) materials originates…
The recent discovery of high-temperature superconductivity in single-layer iron selenide has generated significant experimental interest for optimizing the superconducting properties of iron-based superconductors through the lattice…
Electrides are materials in which some of the electrons are localized at the interstitial sites rather than around the atoms or along atomic bonds. Most elemental electrides are either alkali metals or alkaline-earth metals because of their…
Since the discovery of superconductivity at 200 K in H3S [1] similar or higher transition temperatures, Tcs, have been reported for various hydrogen-rich compounds under ultra-high pressures [2]. Superconductivity was experimentally proved…
The demonstration of a quasi-two-dimensional electron gas (2DEG) and superconducting properties in LaAlO$_3$/SrTiO$_3$ heterostructures has stimulated intense research activity in recent ten years. The 2DEG has unique properties that are…
Advances in theoretical calculations boosted the searches for high temperature superconductors, such as sulfur hydrides and rare-earth polyhydrides. However, the required extremely high pressures for stabilizing these superconductors…
This review discusses the main experiments and theoretical views related to observation of high-temperature superconductivity in intercalated FeSe compounds and single layer films of FeSe on substrates like SrTiO_3. We consider in detail…
The effects of 2.5 MeV electron irradiation were studied in the superconducting phase of single crystals of LaNiGa$_2$, using measurements of electrical transport and radio-frequency magnetic susceptibility. The London penetration depth is…
While hydrogen-rich materials have been demonstrated to exhibit high T$_c$ superconductivity at high pressures, there is an ongoing search for ternary and quaternary hydrides that achieve such high critical temperatures at much lower…
Amongst the iron-based superconductors, LiFeAs is unrivalled in the simplicity of its crystal structure and phase diagram. However, our understanding of this canonical compound suffers from conflict between mutually incompatible…
All non-interacting two-dimensional electronic systems are expected to exhibit an insulating ground state. This conspicuous absence of the metallic phase has been challenged only in the case of low-disorder, low density, semiconducting…
Recently, superconductivity was discovered at very low densities in slightly misaligned graphene multilayers. Surprisingly, despite extremely low electronic density (about $10^{-4}$ electrons per unit cell), these systems realize…