Related papers: c-Axis tunneling in YBa2Cu3O7-\delta/PrBa2Cu3O7-\d…
The recent discovery of high temperature superconductivity in nickelate systems has generated tremendous interests in the field of superconductivity. The core issue to understand the superconductivity mechanism is about the superconducting…
We measure and analyze the resistivity of $Bi_2Sr_2CaCu_2O_{8+\delta}$ crystals for different doping $\delta$. We obtain the fraction of carrier $\eta(T,\delta) = n_g/n_{TOT}$ that do not participate to the c-axis conductivity. All the…
We have recently proposed the s+g wave model for superconducting borocarbides. In spite of a substantial s-wave component, this order parameter exhibits the H^1/2 dependent specific heat and a thermal conductivity linear in H in the vortex…
The superconducting energy gap of $\rm Ba_{1-x}K_xBiO_3$ has been measured by tunneling. Despite the fact that the sample was macroscopically single phase with very sharp superconducting transition $T_c$ at 32~$K$, some of the measured…
We report scanning tunneling spectroscopy imaging of the vortex lattice in single crystalline MgB2. By tunneling parallel to the c-axis, a single superconducting gap (Delta = 2.2 meV) associated with the pi-band is observed. The vortices in…
The far-infrared c-axis conductivity of flux-grown Y$_{1-x}$Pr$_{x}$Ba$_{2}$Cu$_{3}$O$_{7}$ single crystals with 0.2$\leq $x$\leq $0.5 has been studied by sepectral ellipsometry. We find that the c-axis response exhibits spectral features…
The optimally doped and underdoped region of the $t-J$ model at large N (N is the number of spin components) is governed by the competition of d-wave superconductivity (SC) and a d Charge-Density Wave (d-CDW).The partial destruction of the…
The recent discovery of superconductivity in the quasi-one-dimensional compound K$_2$Cr$_3$As$_3$, which consists of double-walled tubes of [(Cr$_3$As$_3$)$^{2-}]^\infty$ that run along the c axis, has attracted immediate attention as a…
We present ellipsometric measurements of the far-infrared dielectric response of polycrystalline samples of the new pnictide superconductor RO0.82F0.18FeAs (R=Nd and Sm). We find evidence that the electronic properties are strongly…
We report a characterization of surfaces of the dichalcogenide TaSe$_2$ using scanning tunneling microscopy and spectroscopy (STM/S) at 150 mK. When the top layer has the 2H structure and the layer immediately below the 1T structure, we…
We report the occurrence of superconductivity, with maximum Tc = 40 K, in superlattices (SLs) based on two insulating oxides, namely CaCuO2 and SrTiO3. In these (CaCuO2)n/(SrTiO3)m SLs, the CuO2 planes belong only to CaCuO2 block, which is…
We present a study of the superconducting properties of the candidate topological superconductor Ti_(3)Sb. Electrical transport measurements show zero resistance with a T_(c,onset) of ~ 5.9 K with a transition width {\Delta}T_c~ 0.6 K. The…
The c-axis tunneling matrix of high-Tc superconductors is shown to depend strongly on the in-plane momentum of electrons and vanish along the four nodal lines of the d(x^2-y^2)-wave energy gap. This anisotropic tunneling matrix suppresses…
The normal state optical conductivity is calculated for a layered metal with two layers per unit cell coupled through a transverse hopping matrix element $t_\perp$. The optical response involves an interband term in addition to the more…
The in-plane and out-of-plane surface impedance and microwave conductivity components of one and the same YBa_2Cu_3O_{7-x} (0.07\le x\le 0.47) single crystal are determined in the wide ranges of temperature T and carrier concentration p in…
We use the three-dimensional Josephson junction array system as a model for studying the temperature dependence of the c-axis resistivity of high temperature superconductors, in the presence of an external magnetic field H applied in the…
We report superconductivity in quasi-1D nanostructures created at the LaAlO3/SrTiO3 interface. Nanostructures having line widths w~10 nm are formed from the parent two-dimensional electron liquid using conductive atomic force microscope…
We report the results of electrical resistivity, magnetic and thermodynamic measurements on polycrystalline SnSb, whose structure consists of stacks of Sb bilayers and Sn4Sb3 septuple layers along the c-axis. The material is found to be a…
We report measurements of the in-plane London penetration depth $\lambda$ in single crystals of the $\alpha$-PdBi$_{2}$ superconductor --- the $\alpha$-phase counterpart of the putative topological superconductor $\beta$-PdBi$_{2}$, down to…
We investigated the structural, electronic, and superconducting properties of Co1-xNixZr2, in which c-axis thermal expansion is systematically controlled. At x (smaller than) 0.3, c-axis negative thermal expansion (NTE) was observed, and…