Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
TT: Fachverband Tiefe Temperaturen
TT 93: Superconductivity: (General) Theory
TT 93.3: Vortrag
Donnerstag, 3. April 2014, 17:00–17:15, HSZ 201
Plasmons, gauge invariance and mass in non-centrosymmetric superconductors — •Nikolaj Bittner1, Dietrich Einzel2, Ludwig Klam1, and Dirk Manske1 — 1Max–Planck–Institut für Festkörperforschung, Heisenbergstraße 1, D–70569 Stuttgart, Germany — 2Walther–Meißner–Institut für Tieftemperaturforschung, Walther–Meißner–Straße 8, D–85748 Garching, Germany
We present for the first time a comprehensive, gauge–invariant description of the order parameter collective modes in the recently discovered non–centrosymmetric superconductors (NCS). The gauge mode (Nambu–Goldstone Boson, ωG), common to all superconductors, and the new collective mode (Leggett mode, ωL), which usually occurs in ordinary two–band superconductors, were specified by employing (Nambu–)matrix kinetic theory in the clean limit. Moreover, we investigate the dispersion and the general role of these collective excitations in NCS systems. In particular, the subtle interplay between the gauge mode and the Leggett mode is analyzed in view of the validity of the charge conservation law. The long–range Coulomb interaction is seen to introduce the condensate plasma frequency ωP into the description of NCS and to distinguish between the order parameter collective modes ωG and ωL with respect to their participation in the Anderson–Higgs mechanism [1,2]. In contrast to ordinary two–band superconductors, the possibility of a mass–less Leggett mode can be predicted to occur in NCS, which simulates the existence of a second gauge mode.
P. W. Anderson, Phys. Rev. 130, 439 (1963)
P. Higgs, Phys. Rev. Lett. 13, 508 (1964)