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Related papers: Anisotropic Migdal-Eliashberg theory using Wannier…

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Maximally-localized Wannier functions are quantum wavefunctions resembling atomic orbitals that are used to describe electrons in condensed matter. Since their introduction in 1997, these functions have become ubiquitous in ab initio…

Computational Physics · Physics 2026-04-09 Sabyasachi Tiwari , Bruno Cucco , Viet-Anh Ha , Feliciano Giustino

Migdal-Eliashberg theory of boson-mediated superconductivity contains a $\sqrt{\lambda}$ divergence in the critical temperature $T_c$ for strong electron-boson coupling $\lambda$. In the conventional Migdal-Eliashberg theory, the…

Strongly Correlated Electrons · Physics 2025-11-21 Nikolay V. Gnezdilov , Rufus Boyack

The variation of the superconducting critical temperature Tc as a function of x in the diboride Mg1-xAlxB2 has been studied in the framework of the two-bands Eliashberg theory and traditional phonon coupling mechanism. We have solved the…

Superconductivity · Physics 2009-11-10 G. A. Ummarino , R. S. Gonnelli , S. Massidda , A. Bianconi

We have studied the electron-phonon and superconducting properties of the Mg{1-x}AlxB2 and MgB{2(1-y)}C{2y} alloys within the framework of density functional theory using the self-consistent virtual-crystal approximation. For both alloys,…

Superconductivity · Physics 2010-12-16 O. De la Peña-Seaman , R. de Coss , R. Heid , K. -P. Bohnen

The mechanisms for strong electron-phonon coupling predicted for hydrogen-rich alloys with high superconducting critical temperature ($T_c$) are examined within the Migdal-Eliashberg theory. Analysis of the functional derivative of $T_c$…

Superconductivity · Physics 2017-09-28 K. Tanaka , J. S. Tse , H. Liu

Ultrawide-bandgap rutile GeO2 is emerging as a promising semiconductor for power electronics, where efficient heat dissipation is essential to suppress self-heating and ensure device reliability. However, the temperature dependence and…

Thermal conductivity measurements can provide key and experimentally verifiable insight into the electronic transport of unconventional superconductors. In this work, electronic thermal transport of two-dimensional tight-binding metallic…

Superconductivity · Physics 2023-08-16 Sean F Peterson , Sourav Sen Choudhury , Yves Idzerda

The superconducting state in vanadium characterizes with the critical temperature ($T_{c}$) equal to $5.3$~K. The Coulomb pseudopotential, calculated with the help of the Eliashberg equations, possesses anomalously high value…

Superconductivity · Physics 2017-07-27 E. A. Drzazga , I. A. Domagalska , M. W. Jarosik , R. Szczȩśniak , J. K. Kalaga

The upper critical field Hc2 is evaluated for weakly-coupled two-band superconductors. By modeling the actual bands and the gap distribution of MgB2 by two Fermi surface spheroids with average parameters of the real material, we show that…

Superconductivity · Physics 2009-11-07 P. Miranovic , K. Machida , V. G. Kogan

In this paper we discuss the normal and superconducting state properties of two pnictide superconductors, LaOFeAs and LaONiAs, using Migdal-Eliashberg theory and density functional perturbation theory. For pure LaOFeAs, the calculated…

Superconductivity · Physics 2015-05-13 L. Boeri , O. V. Dolgov , A. A. Golubov

The instabilities induced on a two-dimensional system of correlated electrons by the anisotropies of its Fermi line are analyzed on general grounds. Simple scaling arguments allow to predict the opening of a superconducting gap with a…

Strongly Correlated Electrons · Physics 2009-10-31 J. Gonzalez , F. Guinea , M. A. H. Vozmediano

Recent work on an electron-phonon model in two-dimensions is reviewed and some new results are presented. We utilize both Quantum Monte Carlo simulations and Migdal-Eliashberg theory. The type of electron-ion coupling considered is on-site.…

Superconductivity · Physics 2021-01-29 F. Marsiglio

We investigate the role of specific phonon mode symmetries for the room temperature superconductivity in atomic hydrogen under large pressure. Using anisotropic Migdal-Eliashberg theory with ab initio input from density functional theory,…

Superconductivity · Physics 2021-03-11 Ashok K. Verma , P. Modak , Fabian Schrodi , Alex Aperis , Peter M. Oppeneer

A theory of phonon-mediated superconductivity in strong-coupling amorphous materials is developed based on an effective description of structural disorder and its effect on the vibrational spectrum. The theory accounts for the…

Superconductivity · Physics 2020-06-05 Matteo Baggioli , Chandan Setty , Alessio Zaccone

In order to understand the unexpected superconducting behavior of MgB$_2$ compound we have made electronic structure calculations for MgB$_2$ and closely related systems. Our calculated Debye temperature from the elastic properties indicate…

Superconductivity · Physics 2009-11-07 P. Ravindran , P. Vajeeston , R. Vidya , A. Kjekshus , H. Fjellvåg

Weyl superconductivity or superfluidity, a fascinating topological state of matter, features novel phenomena such as emergent Weyl fermionic excitations and anomalies. Here we report that an anisotropic Weyl superfluid state can arise as a…

Quantum Gases · Physics 2015-01-30 Bo Liu , Xiaopeng Li , Lan Yin , W. Vincent Liu

It is shown that the famous Allen -- Dynes asymtotic limit for superconducting transition temperature in very strong coupling region $T_{c}>\frac{1}{2\pi}\sqrt{\lambda}\Omega_0$ (where $\lambda\gg 1$ - is Eliashberg - McMillan electron -…

Superconductivity · Physics 2021-07-02 M. V. Sadovskii

The interplay of Anderson localization and electron-electron interactions is known to lead to enhancement of superconductivity due to multifractality of electron wave functions. We develop the theory of multifractally-enhanced…

Superconductivity · Physics 2022-11-23 E. S. Andriyakhina , I. S. Burmistrov

We study the graphite intercalated compound CaC$_6$ by means of Eliashberg theory, focusing on the anisotropy properties. An analysis of the electron-phonon coupling is performed, and we define a minimal 6-band anisotropy structure.…

Superconductivity · Physics 2012-05-15 A. Sanna , S. Pittalis , J. K. Dewhurst , M. Monni , S. Sharma , G. Ummarino , S. Massidda , E. K. U. Gross

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