TY  - JOUR
A1  - Dürrnagel, Matteo
A1  - Beyer, Jacob
A1  - Thomale, Ronny
A1  - Schwemmer, Tilman
T1  - Unconventional superconductivity from weak coupling
JF  - The European Physical Journal B
N2  - We develop a joint formalism and numerical framework for analyzing the superconducting instability of metals from a weak coupling perspective. This encompasses the Kohn–Luttinger formulation of weak coupling renormalization group for superconductivity as well as the random phase approximation imposed on the diagrammatic expansion of the two-particle Green’s function. The central quantity to resolve is the effective interaction in the Cooper channel, for which we develop an optimized numerical framework. Our code is capable of treating generic multi-orbital models in two as well as three spatial dimensions and, in particular, arbitrary avenues of spin-orbit coupling.
KW  - superconducting instability
KW  - metals
KW  - weak coupling
KW  - unconventional superconductivity
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-325153
SN  - 1434-6028
VL  - 95
IS  - 7
ER  - 
TY  - JOUR
A1  - Okada, Michio
A1  - Rotenberg, Eli
A1  - Kevan, S. D.
A1  - Schäfer, J.
A1  - Ujfalussy, Balazs
A1  - Stocks, G. Malcolm
A1  - Genatempo, B.
A1  - Bruno, E.
A1  - Plummer, E. W.
T1  - Evolution of the electronic structure in \(Mo_{1-x}Re_x\) alloys
JF  - New Journal of Physics
N2  - We report a detailed experimental and theoretical study of the electronic structure of \(Mo_{1-x}Re_x\) random alloys. We have measured electronic band dispersions for clean and hydrogen-covered \(Mo_{1-x}Re_x\) ( 110) with x = 0-0.25 using angle-resolved photoemission spectroscopy. Our results suggest that the bulk and most surface electronic bands shift relative to the Fermi level systematically and approximately rigidly with Re concentration. We distinguish and quantify two contributions to these shifts: a raise of the Fermi energy and an increase of the overall bandwidth. Alloy bands calculated using the first-principles Korringa-Kohn-Rostoker coherent-potential-approximation method accurately predict both of these effects. As derived from the rigid band model, the Fermi energy shift is inversely related to the bulk density of states in this energy region. Using our results, we also characterize an electronic topological transition of the bulk Fermi surface and relate this to bulk transport properties. Finally, we distinguish effects beyond the rigid band approximation: a highly surface-localized state and a composition-dependent impact of the spin-orbit interaction.
KW  - topological transitions
KW  - surface state
KW  - metals
KW  - total energy
KW  - W(110)
KW  - hydrogen
KW  - mo
KW  - superconductivity
KW  - spectra
KW  - coherent potential approximation
Y1  - 2013
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-122993
SN  - 1367-2630
VL  - 15
IS  - 093010
ER  -