Nodes vs. minima in the energy gap of iron-pnictides from field-induced anisotropy

Abstract

We develop the formalism for computing the oscillations of the specific heat and thermal transport under rotated magnetic field in multiband superconductors with anisotropic gap and apply it to iron-pnictides. We show that these oscillations change sign at low temperatures and fields, which strongly influences the conclusions about the gap structure based on experiment. We find that recent measurements of the specific heat oscillations indicate that the iron-based superconductors possess an anisotropic gap with deep minima or nodes close to the line connecting electron and hole pockets. We make predictions for the behavior of the thermal conductivity that will help distinguish between these cases.

4+3 pages, published version with supplement

References in corpus (28)

• Superconductivity at 38 K in the iron arsenide (Ba1-xKx)Fe2As2
• Unconventional pairing originating from disconnected Fermi surfaces in superconducting LaFeAsO${}_{1-x}$F${}_x$}
• Observation of Fermi-surface-dependent nodeless superconducting gaps in Ba0.6K0.4Fe2As2
• Near-degeneracy of several pairing channels in multiorbital models for the Fe-pnictides
• Density functional study of FeS, FeSe and FeTe: Electronic structure, magnetism, phonons and superconductivity
• Magnetism, superconductivity, and pairing symmetry in Fe-based superconductors
• To What Extent Iron-Pnictide New Superconductors Have Been Clarified: A Progress Report
• Funtional Renormalization Group Study of the Pairing Symmetry and Pairing Mechanism of the FeAs Based High Temperature Superconductors
• Pairing Symmetry in a Two-Orbital Exchange Coupling Model of Oxypnictides
• Electronic structure of the iron-based superconductor LaOFeP
• Commensurate Spin Density Wave in LaOFeAs: A Local Probe Study
• Spin fluctuations and superconductivity in a 3D tight-binding model for BaFe2As2
• Evidence for nodal superconductivity in LaFePO
• Momentum dependence of the superconducting gap in Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$
• Superconducting gap symmetry of Ba0.6K0.4Fe2As2 studied by angle-resolved photoemission spectroscopy
• Multiple Nodeless Superconducting Gaps in (Ba0.6K0.4)Fe2As2 Superconductor from Angle-Resolved Photoemission Spectroscopy
• Nodal Structure of Unconventional Superconductors Probed by the Angle Resolved Thermal Transport Measurements
• Momentum dependence and nodes of the superconducting gap in iron-pnictides
• Origin of Gap Anisotropy in Spin Fluctuation Models of the Fe-pnictides
• Electronic Structure of Fe-Based Superconductors
• Lifting of nodes by disorder in extended-$s$ state superconductors: application to ferropnictides
• Quantum oscillations in the parent pnictide BaFe${}_2$As${}_2$ : itinerant electrons in the reconstructed state
• Unconventional superconductors under rotating magnetic field I: density of states and specific heat
• Determining gap nodal structures in Fe-based superconductors: angle-dependence of the low temperature specific heat in an applied magnetic field
• Unconventional superconductors under rotating magnetic field II: thermal transport
• Vortex State and Field-Angle Resolved Specific Heat Oscillation for H // ab in d-Wave Superconductors
• Angular resolved specific heat in iron-based superconductors: the case for nodeless extended $s$-wave gap
• Inversion of specific heat oscillations with in-plane magnetic field angle in 2D d-wave superconductors

Cited by in corpus (4)

• Low-energy microscopic models for iron-based superconductors: a review
• ${}^{75}$As NMR of Ba(Fe${}_{0.93}$Co${}_{0.07}$)${}_2$As${}_2$ in High Magnetic Field
• Quasiclassical description of a superconductor with a spin density wave
• Role of Fermi surface anisotropy in the study of gap anisotropy using magnetic-field-angle dependence of thermal oscillations in AyFe2-xSe2 superconductors