2008/02/04 by Yunkyu Bang
Materials Science · Physics and Astronomy · #Iron-based superconductors research #Physics of Superconductivity and Magnetism #Superconductivity in MgB2 and Alloys #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.78.075116
published as Phys. Rev. B 78, 075116 (2008) · 9 pages, 10 figures
arxiv created 2008/02/04 · openalex publication_date 2008/08/19 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We study the effects of phonon interaction on the superconducting pairing in the background of a d-wave gap, mediated by antiferromagnetic (AFM) spin fluctuations, using coupled BCS gap equations. We found that phonon interaction can induce a s-wave component to the d-wave gap in the (D+S) form with an interaction anisotropy and in the (D+iS) form without anisotropy, respectively. In either case, however, Tc is not enhanced compared to the pure d-wave pairing without phonon interaction. On the other hand, anisotropic phonon interaction can dramatically enhance the d-wave pairing itself and therefore Tc, together with the AFM spin fluctuation interaction. This (DAFM+Dph) type pairing exhibits strongly reduced isotope coefficient despite the large enhancement of Tc by phonon interaction. Finally, we study the combined type of (DAFM+Dph+iS) gap and calculate the penetration depth and specific heat to be compared with the experiments.