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This paper presents a brief review on the reported anisotropic properties of MgB2, in the superconducting state (e.g. upper critical field Hc2, field penetration depth, coherence length, energy gap) as well as in the normal state (e.g.,…

Superconductivity · Physics 2007-05-23 O. F. de Lima

We demonstrate that the variation of the Andreev reflection with applied magnetic field provides a direct means of comparing the properties of MgB2 with the theory for a dirty two-band superconductor, and we find good agreement between the…

Superconductivity · Physics 2009-11-11 Y. Bugoslavsky , Y. Miyoshi , G. K. Perkins , A. D. Caplin , L. F. Cohen , A. V. Pogrebnyakov , X. X. Xi

Possible candidates for the Mg2B3Ox nanostructures observed in bulk of polycrystalline MgB2 (Ref.1) have been studied using a combination of Z-contrast imaging, electron energy loss spectroscopy (EELS) and first-principles calculations. The…

Superconductivity · Physics 2009-11-10 Juan C. Idrobo , Serdar Ogut , Taner Yildirim , Robert F. Klie , Nigel D. Browning

The Nambu-Gorkov generalized Hartree-Fock theory of superconductivity is further generalized to treat simultaneously two kinds of correlations: the correlations that lead to superconductivity, as well as the correlations that produce the…

Superconductivity · Physics 2015-06-25 Moshe Dayan

The remarkable field dependence of the electronic thermal conductivity observed in MgB_2 can be explained as a consequence of multi-gap superconductivity. A key point is that for moderately clean samples, the mean free path becomes…

Superconductivity · Physics 2009-11-07 Hiroaki Kusunose , T. M. Rice , Manfred Sigrist

This paper reports an implementation of Hartree-Fock linear response with complex orbitals for computing electronic spectra of molecules in a strong external magnetic fields. The implementation is completely general, allowing for…

Chemical Physics · Physics 2019-02-01 Sangita Sen , Kai K. Lange , Erik I. Tellgren

We report variation of lattice structure in diborides (AB2) with different A atoms to identify the special case of MgB2 showing high Tc superconductivity. High purity MgB2 (Tc~39 K) has been prepared by direct reaction of the elements and…

The multi-configuration Dirac-Hartree-Fock method was employed to calculate the total and excitation energies, oscillator strengths and hyperfine structure constants for low-lying levels of Sm I. In the first-order perturbation…

Atomic Physics · Physics 2015-09-16 Fuyang Zhou , Yizhi Qu , Jiguang Li , Jianguo Wang

A simple approximation within the framework of the hybrid methods for the calculation of the electronic structure of solids is presented. By considering only the diagonal elements of the perturbation operator (Hartree-Fock exchange minus…

Materials Science · Physics 2012-01-31 Fabien Tran

We performed an extensive investigation on the correlations among superconductivity, structural instability and band filling in Nb1-xB2 materials. Structural measurements reveal that a notable phase transformation occurs at x=0.2,…

Superconductivity · Physics 2009-11-11 R. J. Xiao , K. Q. Li , H. X. Yang , G. C. Che , H. R. Zhang , C. Ma , Z. X. Zhao , J. Q. Li

Electron transport properties of few-electron open quantum dots within the spin-restricted Hartree-Fock approximation are studied. The self-consistent numerical calculations were performed for a whole device, including the semi-infinite…

Mesoscale and Nanoscale Physics · Physics 2015-05-27 S. Ihnatsenka

First-principles calculations were performed to investigate electronic and elastic properties of the newly discovered 7.5K superconductor: layered Nb2InC. As a result, electronic bands, total and site-projected l- decomposed DOS at the…

Superconductivity · Physics 2010-04-08 I. R. Shein , A. L. Ivanovskii

Using the numerical unrestricted Hartree-Fock approach, we study the ground state of a two-orbital model describing newly discovered FeAs-based superconductors. We observe the competition of a $(0, \pi)$ mode spin-density wave and the…

Superconductivity · Physics 2015-05-13 Shuo Yang , Wen-Long You , Shi-Jian Gu , Hai-Qing Lin

We have carried out detailed high resolution ARPES measurements and band structure calculations to study the electronic structure of CaMnSb$_{2}$. The observed Fermi surface mainly consists of one hole pocket around ${\Gamma}$ point and one…

The structural electronic and optical properties of intermetallic compound MgRh were investigated by using the ab-initio technique from CASTEP code. In this study we have carried out the pseudo-potential plane-wave (PP-PW) method based on…

Materials Science · Physics 2015-12-08 Md. Lokman Ali , Md. Zahidur Rahaman , Md. Atikur Rahman , Md. Afjalur Rahman

Magnetic properties of metals are investigated through electronic structure calculations based on the recently-proposed magnetic-field-containing relativistic tight-binding approximation (MFRTB) method [Phys. Rev. B \textbf{91}, 075122…

Strongly Correlated Electrons · Physics 2017-05-31 Masahiko Higuchi , Katsuhiko Higuchi

The basic magnetic and electronic properties of most binary compounds have been well known for decades. Therefore the recent announcement of superconductivity at 39 K in the simple binary ceramic compound MgB2 is surprising. This compound,…

Electronic Raman scattering studies on MgB2 single crystals as a function of excitation and polarization have revealed three distinct superconducting features: a clean gap below 37 cm-1 and two coherence peaks at 109 cm-1 and 78 cm-1 which…

Superconductivity · Physics 2007-10-16 G. Blumberg , A. Mialitsin , B. S. Dennis , N. D. Zhigadlo , J. Karpinski

We calculate the energy band structure for electrons in an external periodic potential combined with a perpendicular magnetic field. Electron-electron interactions are included within a Hartree approximation. The calculated energy spectra…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Egidijus Anisimovas , Peter Johansson

Using the Korringa-Kohn-Rostoker coherent-potential approximation in the atomic-sphere approximation (KKR-ASA CPA) we have studied the changes in the electronic structure and the superconducting transition temperature T_{c} in Nb_{1-x}B_{2}…

Superconductivity · Physics 2009-11-10 P. Jiji Thomas Joseph , Prabhakar P. Singh
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