相关论文: Multiple Andreev reflections spectroscopy of two-g…
We consider the minimal two-band model for the Fe-based superconductors with a phenomenological pairing interaction which mimics short-range antiferromagnetic (AFM) fluctuations. Two superconducting (SC) gap solutions are found to exist…
The discovery of high-temperature superconductivity in Fe-based compounds [1,2] has triggered numerous investigations on the interplay between superconductivity and magnetism [3] and, more recently, on the enhancement of transition…
We present the first direct evidence for two-band superconductivity in the quasi-one dimensional chalcogenide Nb$_{2}$Pd$_{0.81}$S$_{5}$. Soft point contact spectroscopic measurements reveal Andreev reflection in the differential…
Andreev reflection is investigated in layered anisotropic normal metal / superconductor (N/S) systems in the case of an energy gap \Delta in S not negligible with respect to the Fermi energy E_F, as it probably occurs with high critical…
We present our investigations on the superconducting properties of monolayers of FeSe$_{0.5}$Te$_{0.5}$ grown on the 3D topological insulator Bi$_{2}$Se$_{1.2}$Te$_{1.8}$ using low temperature scanning tunneling spectroscopy (STS). While…
We have performed a low temperature scanning tunneling microscopy and spectroscopy study of the iron chalcogenide superconductor FeSe_{0.4}Te_{0.6} with T_{C}~14 K. Spatially resolved measurements of the superconducting gap reveal…
We have investigated the superconducting ground state of the newly discovered superconductor ThFeAsN with a tetragonal layered crystal structure using resistivity, magnetization, heat capacity and transverse-field (TF) muon-spin rotation…
We perform a point-contact Andreev reflection spectroscopic study of the topological superconducting material, Cu0.25Bi2Se3, in the ballistic regime using a normal-metal gold tip. We observe distinct point-contact spectra on the…
We study Fe$_{1+y}$Te$_{0.6}$Se$_{0.4}$ multi-band superconductor with $T_c=14$K by polarization-resolved Raman spectroscopy. Deep in the superconducting state, we detect pair-breaking excitation at 45cm$^{-1}$ ($2\Delta=5.6$meV) in the…
This paper reports the synthesis and superconducting behaviors of the tetragonal iron-chalcogenide superconductor FeSe. The electrical resistivity and magnetic moment measurements confirmed its superconductivity with a $T_c^{zero}$ and…
High-resolution angle-resolved photoemission measurements were taken on FeSe$_{1-x}$S$_x$ (x=0, 0.04, and 0.08) superconductors. With an ultrahigh energy resolution of 0.4 meV, unusual two hole bands near the Brillouin-zone center, which…
Superconducting EuFe2(As0.82P0.18)2 single crystals are investigated by infrared spectroscopy in a wide frequency range. Below Tc=28K a superconducting gap forms at 2\Delta_{0} = 9.5 meV = 3.8 k_B T_c causing the reflectivity to sharply…
Point-contact (PC) investigations on the title compound in the normal and superconducting (SC) state (Tc=10,6 K) are presented. The temperature dependence of the SC gap of TmNi2B2C determined from Andreev-reflection (AR) spectra using the…
The discovery of high-transition temperature (high-Tc) superconductivity near antiferromagnetism in iron arsenides raised the possibility of an unconventional superconducting mechansim1-8. The observation of clear Fermi surfaces and…
Here presented a systematic study of superconductor-constriction-superconductor contacts realized by a break-junction technique in layered superconductors. Depending on the constriction transparency the tunneling and SnS-Andreev…
Scanning tunneling microscopy/spectroscopy (STM/STS) measurements were carried out on a multi-layered cuprate superconductor Ba$_2$Ca$_5$Cu$_6$O$_{12}$(O$_{1-x}$,F$_x$)$_2$. STM topography revealed random spot structures with the…
Here we report an optical investigation in the terahertz region of a 40 nm ultrathin BaFe$_{1.84}$Co$_{0.16}$As$_2$ superconducting film with superconducting transition temperature T$_c$ = 17.5 K. A detailed analysis of the combined…
We report 31P-NMR and specific heat measurements on an iron (Fe)-based superconductor SrFe2(As0.65P0.35)2 with Tc=26 K, which have revealed the development of antiferromagnetic correlations in the normal state and the unconventional…
The recent discovery of superconductivity in iron-arsenic compounds below a transition temperature (Tc) as high as 55K ended the monopoly of copper oxides (cuprates) in the family of high-Tc superconductors. A critical issue in…
The Andreev Reflection is the key mechanism for the superconducting proximity effect. It provides phase correlations in a system of non-interacting electrons at mesoscopic scales, i.e. over distances much larger than the microscopic lengths…