English
Related papers

Related papers: Direct evidence for a multiple superconducting gap…

200 papers

We have performed high-resolution photoemission spectroscopy on MgB2 and observed opening of a superconducting gap with a narrow coherent peak. We found that the superconducting gap is s-like with the gap value of 4.5 meV at 15 K. The…

Strongly Correlated Electrons · Physics 2009-11-07 T. Takahashi , T. Sato , S. Souma , T. Muranaka , J. Akimitsu

The superconducting gap of MgB2 has been studied by high-resolution angle-resolved photoemission spectroscopy (ARPES). The momentum(k)-resolving capability of ARPES enables us to identify the s- and p-orbital derived bands predicted from…

Superconductivity · Physics 2007-05-23 S. Tsuda , T. Yokoya , Y. Takano , H. Kito , A. Matsushita , F. Yin , H. Harima , S. Shin

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

Far-infrared reflectivity studies on the polycrystalline intermetallic compound MgB_2 with a superconducting transition temperature T_c=39 K were performed at temperatures 20 K to 300 K. We observe a significant raise of the…

Experimental support is found for the multiband model of the superconductivity in the recently discovered system MgB2 with the transition temperature Tc = 39 K. By means of Andreev reflection evidence is obtained for two distinct…

Superconductivity · Physics 2009-02-12 P. Szabo , P. Samuely , J. Kacmarcik , Th. Klein , J. Marcus , D. Fruchart , S. Miraglia , C. Marcenat , A. G. M. Jansen

The study of the anisotropic superconductor MgB2 using a combination of scanning tunneling microscopy and spectroscopy reveals two distinct energy gaps at Delta1=2.3 meV and Delta2=7.1 meV. Different spectral weights of the partial…

Superconductivity · Physics 2009-11-07 M. Iavarone , G. Karapetrov , A. E. Koshelev , W. K. Kwok , G. W. Crabtree , D. G. Hinks

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 scanning tunneling spectroscopy (STS) measurements of the gap properties of both ceramic MgB2 and c-axis oriented epitaxial MgB2 thin films. Both show a temperature dependent zero bias conductance peak and evidence for two…

Point-contact spectroscopy measurements on magnesium diboride reveal the existence of two superconducting energy gaps closing at the same transition temperature in line with the multiband model of superconductivity. The sizes of the two…

Superconductivity · Physics 2009-11-07 P. Samuely , P. Szabo , J. Kacmarcik , T. Klein , A. G. M. Jansen

Far-infrared reflectance of a MgB2 film has been measured by Fourier-transform spectroscopy for frequencies 10 cm^{-1}<\nu <4000 cm^{-1} above and below the superconducting transition. The data provide clear experimental evidence for the…

Superconductivity · Physics 2009-11-07 A. Pimenov , A. Loidl , S. I. Krasnosvobodtsev

We have measured the Raman spectra of polycrystalline MgB$_{2}$ from 25 {\cm} to 1200 {\cm}. When the temperature was decreased below the superconducting transition temperature $T_c$, we observed a superconductivity-induced redistribution…

Superconductivity · Physics 2016-08-31 X. K. Chen , M. J. Konstantinovic , J. C. Irwin , D. D. Lawrie , J. P. Franck

We report on tunneling spectroscopy experiments in small grains of the new binary intermetallic superconductor MgB2. Experiments have been performed at 2.5 K using a low temperature scanning tunneling microscope. Good fit to the BCS model…

Superconductivity · Physics 2009-11-07 Gabino Rubio-Bollinger , Hermann Suderow , Sebastian Vieira

We present extensive Scanning Tunneling Spectroscopy (STM/S) measurements at low temperatures in the multiband superconductor MgB$_2$. We find a similar behavior in single crystalline samples and in single grains, which clearly shows the…

Superconductivity · Physics 2009-11-07 P. Martinez-Samper , J. G. Rodrigo , G. Rubio-Bollinger , H. Suderow , S. Vieira , S. Lee , S. Tajima

We performed point-contact spectroscopy on the binary superconductor MgB$_2$. The differential conductance shows gap-related structures which vary in width and position from contact to contact. The distribution of energy gaps shows a…

Superconductivity · Physics 2009-11-07 F. Laube , G. Goll , J. Hagel , H. v. Löhneysen , D. Ernst , T. Wolf

The Andreev reflection measurements of the superconducting energy gap in the carbon-substituted MgB$_2$ are presented. Despite the strong suppression of the transition temperature by 17 K in comparison with the pure MgB$_2$, the same…

Superconductivity · Physics 2009-11-10 P. Samuely , Z. Holanova , P. Szabo , J. Kacmarcik , R. A. Ribeiro , S. L. Bud'ko , P. C. Canfield

We present scanning tunneling microscopy measurements of the surface of superconducting MgB2 with a critical temperature of 39K. In zero magnetic field the conductance spectra can be analyzed in terms of the standard BCS theory with a…

Superconductivity · Physics 2009-11-07 G. Karapetrov , M. Iavarone , W. K. Kwok , G. W. Crabtree , D. G. Hinks

``Sub-meV'' resolution photoemission spectroscopy was used to study carbon-substitution dependence on the multiple superconducting gap of Mg(B$_{1 - x}$C$_{x})_{2}$. Two features corresponding to $\sigma $ and $\pi $ gaps are clearly…

Superconductivity · Physics 2009-11-10 S. Tsuda , T. Yokoya , T. Kiss , T. Shimojima , S. Shin , T. Togashi , S. Watanabe , C. Chen , S. Lee , H. Uchiyama , S. Tajima , N. Nakai , K. Machida

We have studied the structure of the superconducting gap in MgB2 thin films by means of point-contact spectroscopy using a gold tip. The films were produced by depositing pure boron on a sapphire substrate, using e-beam evaporation,…

We studied the far-infrared reflectance of superconducting MgB2 in and out of equilibrium using pulsed synchrotron radiation. The equilibrium data can be described by a single energy gap at 2 Delta / hc = 43 cm-1. The fit improves slightly…

Superconductivity · Physics 2007-05-23 R. P. S. M. Lobo , J. J. Tu , Eun-Mi Choi , Hyeong-Jin Kim , W. N. Kang , Sung-Ik Lee , G. L. Carr

We show that the specific heat of the superconductor MgB_2 (MgB2) in zero field, for which significant non-BCS features have been reported, can be fitted, essentially within experimental error, over the entire range of temperature to T_c by…

Superconductivity · Physics 2009-11-07 F. Bouquet , Y. Wang , R. A. Fisher , D. G. Hinks , J. D. Jorgensen , A. Junod , N. E. Phillips
‹ Prev 1 2 3 10 Next ›