Тип публикации: статья из журнала
Год издания: 2012
Идентификатор DOI: 10.1103/PhysRevB.85.014511
Аннотация: We revisit the issue of the gap symmetry in KFe2As2, which is an Fe pnictide superconductor with only hole pockets. Previous theoretical studies mostly argued for a d-wave gap in KFe2As2 since transport and thermodynamic measurements point to the presence of the gap nodes. However, a d-wave gap is inconsistent with recent laser-basПоказать полностьюed angle-resolved photoemission measurements. We propose a scenario for a nodal s-wave superconductivity induced by a nonmagnetic intraband and interband interactions between fermions near hole pockets. The superconducting gap changes sign between the hole pockets and has cos 4 theta angular dependence and accidental nodes on one or several hole pockets. We argue that strong angle dependence is the consequence of near-degeneracy between interpocket and intrapocket interaction on the hole pockets. We also analyze the cos 4 theta angular dependence of the gap in other Fe pnictides and compare theoretical results with the photoemission experiments of LiFeAs.
Журнал: PHYSICAL REVIEW B
Выпуск журнала: Vol. 85, Is. 1
ISSN журнала: 24699950
Место издания: COLLEGE PK
Издатель: AMER PHYSICAL SOC