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Related papers: Electron-Phonon Properties of Pnictide Superconduc…

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Based on results from femtosecond time-resolved photoemission, we compare three different methods for determination of the electron-phonon coupling constant {\lambda} in Eu and Ba-based 122 FeAs compounds. We find good agreement between all…

Superconductivity · Physics 2013-08-13 L. Rettig , R. Cortés , H. S. Jeevan , P. Gegenwart , T. Wolf , J. Fink , U. Bovensiepen

The transient response of Ba(Fe(1-x)Co(x))2As2, x=0.08 was studied by pump-probe optical reflectivity. After ultrafast photoexcitation, hot electrons were found to relax with two different characteristic times, indicating the presence of…

Eliashberg's foundational theory of superconductivity is based on the application of Migdal's approximation, which states that vertex corrections to first order electron-phonon scattering are negligible if the ratio between phonon and…

Superconductivity · Physics 2021-02-26 Fabian Schrodi , Alex Aperis , Peter M. Oppeneer

We present a first principles investigation of the lattice dynamics and electron-phonon coupling of the high-T_c superconductor YBa_2Cu_3O_7 within the framework of density functional perturbation theory using a mixed-basis pseudopotential…

Superconductivity · Physics 2009-11-07 K. -P. Bohnen , R. Heid , M. Krauss

The coupling strengths for intra- and inter-band electron-phonon pair scattering are calculated for LiFeAs. While the sum of these couplings, which gives the total electron-phonon coupling $\lambda$, is of order 0.2, we find that their…

Superconductivity · Physics 2015-06-16 R. A. Jishi , Douglas Scalapino

I present the results of first principles calculations of the phonon dispersions and electron-phonon coupling for BaTi$_2$Sb$_2$O. The phonon dispersions show a weak lattice instability near the zone corners that leads to a charge-density…

Superconductivity · Physics 2013-02-18 Alaska Subedi

We show that electron-phonon coupling can induce strong electron pairing in an FeSe monolayer on a SrTiO3 substrate (experimental indications for superconducting Tc are between 65 and 109K). The role of the SrTiO3 substrate in increasing…

Superconductivity · Physics 2015-07-27 Sinisa Coh , Marvin L. Cohen , Steven G. Louie

Eliashberg - McMillan theory of superconductivity is essentially based on the adiabatic approximation. Small parameter of perturbation theory is given by $\lambda\frac{\Omega_0}{E_F}\ll 1$, where $\lambda$ is the dimensionless electron -…

Superconductivity · Physics 2019-04-08 M. V. Sadovskii

Recently superconductivity has been discovered at around 200~K in a hydrogen sulfide system and around 260~K in a lanthanum hydride system, both under pressures of about 200 GPa. These record-breaking transition temperatures bring within…

Superconductivity · Physics 2020-07-15 Sabri Elatresh , T. Timusk , E. J. Nicol

Utilizing Migdal-Eliashberg theory of superconductivity within the first-principles calculations, we work out the role of electron-phonon coupling (EPC) and anisotropic superconducting properties of a recently discovered [Appl. Phys. Lett.…

Superconductivity · Physics 2024-07-11 Shubham Patel , Soumyasree Jena , A Taraphder

The electronic structure, phonons, electron-phonon coupling, and superconductivity are theoretically studied in noncentrosymmetric superconductor ThCoC$_2$ as a function of pressure, in the pressure range 0 - 20 GPa. We found that the…

Superconductivity · Physics 2022-07-01 Gabriel Kuderowicz , Paweł Wójcik , Bartlomiej Wiendlocha

Two simple bounds on the $T_c$ of conventional, phonon-mediated superconductors are derived within the framework of Eliashberg theory in the strong coupling regime. The first bound is set by the total electron-phonon coupling available…

Superconductivity · Physics 2025-10-07 Jonathan E. Moussa , Marvin L. Cohen

The superconductor at the LaAlO3-SrTiO3 interface provides a model system for the study of two-dimensional superconductivity in the dilute carrier density limit. Here we experimentally address the pairing mechanism in this superconductor.…

In this work, we present a comparative first principles study of mechanical properties, electronic structure, phonon dispersion relation, electron-phonon coupling and magnetism in three isostructural superconductors, namely, ThFeAsN,…

Superconductivity · Physics 2021-01-04 Smritijit Sen , Guang-Yu Guo

By means of the first-principles density-functional theory calculation and Wannier interpolation, electron-phonon coupling and superconductivity are systematically explored for boron-doped LiBC (i.e. LiB$_{1+x}$C$_{1-x}$), with $x$ between…

Superconductivity · Physics 2018-06-29 Qi-Zhi Li , Xun-Wang Yan , Miao Gao , Jun Wang

We have analysed optical reflectivity data for Ba_{1-x}K_xBiO_3 in the far-infrared region using Migdal-Eliashberg theory and found it inconsistent with standard electron-phonon coupling: Whereas the superconducting state data could be…

Superconductivity · Physics 2009-10-31 H. J. Kaufmann , O. V. Dolgov , E. K. H. Salje

The electron-phonon coupling of LaO$_{1-x}$F$_x$FeAs is re-investigated on the basis of density functional theory in local density approximation. The implications of the $(\pi,\pi)$ nesting of the Fermi surfaces are carefully studied and…

Superconductivity · Physics 2008-04-11 Helmut Eschrig

The lattice dynamical properties of Li$_x$BC are calculated for several values of $x$ using density functional perturbation theory. We find that the electron-phonon coupling parameter $\lambda$ increases monotonically with decreasing $x$ to…

Superconductivity · Physics 2009-11-07 J. K. Dewhurst , S. Sharma , C. Ambrosch-Draxl , B. Johansson

Superconductivity in novel bismuth-sulphur superconductors has attracted large research efforts, both experimental and theoretical, but a consensus on the nature of superconductivity in these materials has yet to be reached. Using density…

Superconductivity · Physics 2017-05-24 Corentin Morice , Ryosuke Akashi , Takashi Koretsune , Siddharth S. Saxena , Ryotaro Arita

We have synthesized oxygen-deficient fluorine-doped samples of nominal composition PrFeAsO$_{1-x}$F$_y$ to study the normal and superconducting state properties. Resistivity of undoped PrFeAsO exhibits a strong anomaly at around 155 K due…

Superconductivity · Physics 2009-11-13 D. Bhoi , P. Mandal , P. Choudhury