English
Related papers

Related papers: Evidence for Scattering-Dependent Multigap Superco…

200 papers

Granular superconductivity occurs when microscopic superconducting grains are separated by non-superconducting regions through which they communicate by Josephson tunneling to establish the macroscopic superconducting state [1]. Although…

Strongly Correlated Electrons · Physics 2009-11-07 K. M. Lang , V. Madhavan , J. E. Hoffman , E. W. Hudson , H. Eisaki , S. Uchida , J. C. Davis

Scanning tunneling spectroscopic studies of $Ba(Fe_{1-x}Co_x)_2As_2$ (x = 0.06, 0.12) single crystals reveal direct evidence for predominantly two-gap superconductivity. These gaps decrease with increasing temperature and vanish above the…

Strongly Correlated Electrons · Physics 2011-03-29 M. L. Teague , G. K. Drayna , G. P. Lockhart , P. Cheng , B. Shen , H. -H. Wen , N. -C. Yeh

We have investigated theoretically the conductance of a Normal-Superconductor point-contact in the tunnel limit and analyzed the quantum interference effects originating from the scattering of quasiparticles by point-like defects.…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Ye. S. Avotina , Yu. A. Kolesnichenko , J. M. van Ruitenbeek

Scanning tunneling spectroscopy of the high-Tc superconductor Bi2Sr2CaCu2O8+d reveals weak, incommensurate, spatial modulations in the tunneling conductance. Images of these energy-dependent modulations are Fourier analyzed to yield the…

Superconductivity · Physics 2009-11-07 J. E. Hoffman , K. McElroy , D. -H. Lee , K. M Lang , H. Eisaki , S. Uchida , J. C. Davis

We present scanning tunneling spectroscopy measurements of the local quasiparticles' excitation spectra of CeCoIn$_5$ between 440mK and 3K in samples with a bulk $T_{\rm c}=2.25$K. The spectral shape of our low-temperature tunneling data,…

Superconductivity · Physics 2020-07-14 Y. Fasano , P. Szabó , J. Kačmarčík , Z. Pribulová , P. Pedrazzini , P. Samuely , V. F. Correa

We propose a model of quasiparticle tunneling across the high-$T_c$ superconductor-insulator-normal metal junction based on the different mechanisms for tunneling of electrons at positive bias and dissociating polaronic Cooper pairs and…

Superconductivity · Physics 2011-06-08 S. Dzhumanov , O. K. Ganiev , Sh. S. Djumanov

Recent tunneling studies in Bi2Sr2CaCu2O8 suggest that the pseudogap is caused by superconducting fluctuations. By reanalyzing this data, we show that instead there is a second non-superconducting component of the gap which increases…

Superconductivity · Physics 2007-05-23 R. S. Markiewicz , C. Kusko

Non-local conductance experiments using tunnel junctions can provide valuable spectroscopic information on both the transport and relaxation of quasiparticles in superconductors, as these techniques directly probe the quasiparticle charge…

Superconductivity · Physics 2026-04-30 Kevin M. Ryan , Detlef Beckmann , Venkat Chandrasekhar

A complete knowledge of its excitation spectrum could greatly benefit efforts to understand the unusual form of superconductivity occurring in the lightly hole-doped copper-oxides. Here we use tunnelling spectroscopy to measure the T\to 0…

Planar tunneling junctions of the presumably unconventional superconductor FeSe were prepared and investigated. The junctions consisted of FeSe/AlOx/Ag multilayers patterned lithographically into mesa structures. Bias voltage dependent…

Superconductivity · Physics 2018-01-30 Eike Venzmer , Alexander Kronenberg , Martin Jourdan

We present scanning tunneling microscopy and spectroscopy of the newly discovered superconductor CaC$_6$. The tunneling conductance spectra, measured between 3 K and 15 K, show a clear superconducting gap in the quasiparticle density of…

Superconductivity · Physics 2009-11-11 N. Bergeal , V. Dubost , Y. Noat , W. Sacks , D. Roditchev , N. Emery , C. Herold , J-F. Mareche , P. Lagrange , G. Loupias

We report first-principles calculations of the k- and T-dependent superconducting gap Delta(k,T) in MgB2 and its manifestation in various measured quantities. Because the Fermi surface has disconnected sheets with different electron-phonon…

Superconductivity · Physics 2007-05-23 Hyoung Joon Choi , David Roundy , Hong Sun , Marvin L. Cohen , Steven G. Louie

Superconductivity-induced changes in the electronic Raman scattering response were observed for the RNi$_2$B$_2$C (R = Y, Lu) system in different scattering geometries. In the superconducting state, 2$\Delta$-like peaks were observed in…

Superconductivity · Physics 2009-10-31 In-Sang Yang , M. V. Klein , S. L. Cooper , P. C. Canfield , B. K. Cho , Sung-Ik Lee

Using scanning tunneling spectroscopy at T = 4.2 K, we perform simultaneously the topographic imaging and the quasiparticle density of states (DOS) mapping in granular MgB2. We observe a new type of spectrum, showing a pronounced double…

Superconductivity · Physics 2009-11-07 F. Giubileo , D. Roditchev , W. Sacks , R. Lamy , J. Klein

We report on the Andreev spectroscopy and specific heat of high-quality single crystals BaFe$_{1.9}$Ni$_{0.1}$As$_{2}$. The intrinsic multiple Andreev reflection spectroscopy reveals two anisotropic superconducting gaps $\Delta_L \approx…

The recent discovery of superconductivity in pressure-stabilized bulk La3Ni2O7-delta, with a critical temperature (Tc) exceeding 77 K, has opened a new frontier in high-temperature superconductivity research beyond cuprates. Yet, the…

We use tunable laser based Angle Resolved Photoemission Spectroscopy to study the electronic structure of the multi-band superconductor, MgB2. These results form the base line for detailed studies of superconductivity in multi-band systems.…

Superconductivity · Physics 2017-03-21 Daixiang Mou , Rui Jiang , Valentin Taufour , S. L. Bud'ko , P. C. Canfield , Adam Kaminski

We measured the THz reflectance properties of a high quality epitaxial thin film of the Fe-based superconductor BaFe$_{1.84}$Co$_{0.16}$As$_2$ with T$_c$=22.5 K. The film was grown by pulsed laser deposition on a DyScO$_3$ substrate with an…

Scanning tunneling spectroscopy was performed on c-axis Y{1-x}Ca{x}Ba2Cu3O{7-delta} thin films for x= 0, 0.05, 0.15 and 0.20 at 4.2K. The measured spectra show main-gap, sub-gap and satellite features which scale similarly in energy versus…

Superconductivity · Physics 2009-11-13 J. H. Ngai , W. A. Atkinson , J. Y. T. Wei

The heating-compensated interlayer tunneling spectroscopy is performed on stacks of Bi$_2$Sr$_2$CaCu$_2$O$_{8+x}$ intrinsic junctions. The high-accuracy spectra without the local heating, for varying temperatures and magnetic fields, reveal…

Superconductivity · Physics 2007-05-23 Myung-Ho Bae , Jae-Hyun Choi , Hu-Jong Lee , Kee-Su Park