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Related papers: A first-principles study of MgB2 (0001) surfaces

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Monofilamentary MgB2-wires with a mechanical tough Nb/Cu/steel or Fe/steel sheath were prepared and characterized. The steel content was varied to investigate the reinforcement effect and the consequences for the superconducting properties…

Superconductivity · Physics 2009-11-07 W. Goldacker , S. I. Schlachter

A plane-wave density functional theory is used to predict the work functions of Au/Mg decorated Au(100), Mg(001), and stochiometric AuMg alloy surfaces. We find, that irrespective of the details, all Au/Mg systems containing Mg on the…

Materials Science · Physics 2014-09-09 Matúš Dubecký , František Dubecký

First-principles methods have recently established themselves in the field of photocathode research to provide microscopic, quantum-mechanical characterization of relevant materials for electron sources. While most of the existing studies…

Materials Science · Physics 2022-12-19 Richard Schier , Holger-Dietrich Sassnick , Caterina Cocchi

The minimal magnetic field $H_{c2}$ destroying superconductivity in the {\it bulk} of a superconductor is smaller than the magnetic field $H_{c3}$ needed to destroy {\it surface} superconductivity if the surface of the superconductor…

Superconductivity · Physics 2007-05-23 Denis A. Gorokhov

Trigonal PtBi$_2$ is a layered semimetal without inversion symmetry, featuring 12 Weyl points in the vicinity of the Fermi energy. Its topological Fermi arcs were recently shown to superconduct at low temperatures where bulk…

A c-axis oriented thin film and a high density sintered pellet of MgB2 have been studied by x-ray photoemission spectroscopy, and compared to measurements from MgO and MgF2 single crystals. The as-grown surface has a layer which is Mg-rich…

Superconductivity · Physics 2009-11-07 R. P. Vasquez , C. U. Jung , Min-Seok Park , Heon-Jung Kim , J. Y. Kim , Sung-Ik Lee

Precursor MgB2 thin films were prepared on sapphire substrates by magnetron sputtering. Influence of ex-situ annealing process on superconducting MgB2 thin films roughness is discussed. Optimized annealing process of MgB precursor thin…

We present a Ginzburg-Landau theory for a two-band superconductor with emphasis on MgB$_{2}$. Experiments are proposed which lead to identification of the possible scenarios: whether both $\sigma $- and $\pi $-bands superconduct or $\sigma…

Superconductivity · Physics 2007-05-23 V. A. Ivanov , J. J. Betouras , F. M. Peeters

The electronic structure of various (001), (110), and (111)B surfaces of n-type InSb were studied with scanning tunneling microscopy and spectroscopy. The InSb(111)B (3x1) surface reconstruction is determined to be a disordered (111)B (3x3)…

The microscopic superconductivity theory in MgB2 systems in the magnetic fields directed parallel and perpendicular to the plane (ab) is built. The two energy bands of different dimensions overlapping on the Fermi surface (two-dimensional…

Superconductivity · Physics 2008-11-07 M. E. Palistrant , I. D. Cebotari , V. A. Ursu

We present electronic structure calculations together with resistivity, susceptibility, and specific heat measurements for TaB$_2$ to search for the recently contradictorily reported superconductivity and to study related normal state…

Superconductivity · Physics 2009-11-07 H. Rosner , W. E. Pickett , S. -L. Drechsler , A. Handstein , G. Behr , G. Fuchs , K. Nenkov , K. -H. Müller , H. Eschrig

A computational study of the epitaxial Co2MnSi(001)/MgO(001) interface relevant to tunneling magnetoresistive (TMR) devices is presented. Employing ab initio atomistic thermodynamics, we show that the Co- or MnSi-planes of bulk-terminated…

Materials Science · Physics 2009-08-03 B. Hülsen , M. Scheffler , P. Kratzer

We have performed microwave measurements on superconducting hot-isostatically- pressed (HIPed) bulk MgB2 using a parallel-plate resonator technique. The high density and strength of the HIPed material allowed preparation of samples with…

Point contact junctions made from two pieces of MgB2 can be adjusted to exhibit either superconductor-insulator-superconductor (SIS) or superconductor-normal metal-superconductor (SNS) current-voltage characteristics. The SIS…

Superconductivity · Physics 2009-11-07 Y. Zhang , D. Kinion , J. Chen , D. G. Hinks , G. W. Crabtree , John Clarke

We study the effects of pressure on the electron-phonon interaction in MgB_2 using density-functional-based methods. Our results show that the superconductivity in MgB_2 vanishes by 100 GPa, and then reappears at higher pressures. In…

Superconductivity · Physics 2009-11-11 Prabhakar P. Singh

Superconducting mechanism mediated by interband exchange Coulomb repulsion is examined in an extended two-band Hubbard models with a wide band crossing the Fermi level and coexisting with a narrower band located at moderately lower energy.…

Superconductivity · Physics 2007-05-23 Masatoshi Imada

In order to increase the accelerating gradient of Superconducting Radio Frequency (SRF) cavities, Magnesium Diboride (MgB2) opens up hope because of its high transition temperature and potential for low surface resistance in the high RF…

Superconductivity · Physics 2015-06-04 Tamin Tai , Behnood G. Ghamsari , Steven M. Anlage , C. G. Zhuang , X. X. Xi

From first-principles density functional theory calculations, we propose hexagonal layered MgB$_3$C$_3$ as a potential phonon-mediated superconductor at 59 K, which is far higher than the superconductivity of MgB$_2$ ($\approx$ 39 K). The…

Superconductivity · Physics 2023-04-05 Truong-Tho Pham , Duc-Long Nguyen

We report measurements on MgB2 up to ~40GPa. Increasing pressure yields a monotonous decrease of the lattice parameters and of the c/a ratio, but no structural transition down to parameters smaller than those of AlB2. The transition…

In this paper, we reported the structural properties and superconductivity of Mg(B1-xCx)2 compounds. Powder x-ray diffraction results indicate that the samples crystallize in a hexagonal AlB2-type structure. Due to the chemical activity of…

Materials Science · Physics 2009-11-07 Shao-ying Zhang , Jian Zhang , Tong-yun Zhao , Chuan-bing Rong , Bao-gen Shen , Zhao-hua Cheng