Nodal gap in iron-based superconductor CsFe${}_2$As${}_2$ probed by quasiparticle heat transport

Abstract

The thermal conductivity of iron-based superconductor CsFe${}_2$As${}_2$ single crystal ($T_c=$ 1.81 K) was measured down to 50 mK. A significant residual linear term ${\kappa }_0/T$ = 1.27 mW K${}^{-2}$ cm${}^{-1}$ is observed in zero magnetic field, which is about 1/10 of the normal-state value in upper critical field $H_{c2}$. In low magnetic field, ${\kappa }_0/T$ increases rapidly with field. The overall field dependence of ${\kappa }_0/T$ for our CsFe${}_2$As${}_2$ (with residual resistivity ${\rho }_0$ = 1.80 $\mu \Omega$ cm) lies between the dirty KFe${}_2$As${}_2$ (with ${\rho }_0$ = 3.32 $\mu \Omega$ cm) and the clean KFe${}_2$As${}_2$ (with ${\rho }_0$ = 0.21 $\mu \Omega$ cm). These results strongly suggest nodal superconducting gap in CsFe${}_2$As${}_2$, similar to its sister compound KFe${}_2$As${}_2$.

5 pages, 4 figures, accepted for publication in Phys. Rev. B

References in corpus (12)

• Superconductivity at 43 K in Samarium-arsenide Oxides $SmFeAs{O}_{1-x}{F}_x$
• Observation of Fermi-surface-dependent nodeless superconducting gaps in Ba0.6K0.4Fe2As2
• Superconductivity up to 37 K in (A1-xSrx)Fe2As2 with A=K and Cs
• Heavily electron-doped electronic structure and isotropic superconducting gap in AxFe2Se2 (A=K,Cs)
• Evidence for nodal superconductivity in LaFePO
• Universal heat conduction in the iron-arsenide superconductor KFe2As2 : Evidence of a d-wave state
• Unconventional Anisotropic s-Wave Superconducting Gaps of LiFeAs Iron-Pnictide Superconductor
• Strong nodeless pairing on separate electron Fermi surface sheets in (Tl, K)Fe${}_{1.78}$Se${}_2$ probed by ARPES
• Quasiparticle Heat Transport in Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$: Evidence for a k-dependent Superconducting Gap without Nodes
• Evidence for a cos(4φ) Modulation of the Superconducting Energy Gap of Optimally Doped FeTe_{0.6}Se_{0.4} Single Crystals Using Laser Angle-Resolved Photoemission Spectroscopy
• Superfluid density and superconducting gaps of RbFe_{2}As_{2} as a function of hydrostatic pressure
• Evidence for nodeless superconducting gap in NaFe${}_{1-x}$Co${}_x$As from low-temperature thermal conductivity measurements

Cited by in corpus (22)

• High Temperature Superconductivity in Iron Pnictides and Chalcogenides
• Quantum criticality in AFe2As2 with A = K, Rb, and Cs suppresses superconductivity
• Microscopic nature of correlations in multi-orbital AFe2As2 (A=K, Rb, Cs): Hund's coupling versus Coulomb repulsion
• Unconventional superconductivity in the layered iron germanide YFe${}_2$Ge${}_2$
• Two-gap superconductivity with line nodes in CsCa${}_2$Fe${}_4$As${}_4$F${}_2$
• Sudden reversal in the pressure dependence of Tc in the iron-based superconductor CsFe2As2: A possible link between inelastic scattering and pairing symmetry
• Calorimetric study in single crystal of CsFe${}_2$As${}_2$
• Heat transport in RbFe2As2 single crystal: evidence for nodal superconducting gap
• A brief review on muSR studies of unconventional Fe and Cr-based superconductors
• Multigap nodeless superconductivity in CsCa2Fe4As4F2 probed by heat transport
• Nodal superconductivity in FeS: Evidence from quasiparticle heat transport
• Ab-initio perspective on structural and electronic properties of iron-based superconductors
• Probing the pairing symmetry in the over-doped Fe-based superconductor Ba_0.35Rb_0.65Fe_2As_2 as a function of hydrostatic pressure
• Pressure dependence of coherence-incoherence crossover behavior in KFe2As2 observed by resistivity and 75As-NMR/NQR
• Evolution of quasiparticle excitations with critical mass enhancement in superconducting AFe2As2 (A = K, Rb, and Cs)
• Higher-order topological semimetals and nodal superconductors with an order-two crystalline symmetry
• Increasing stripe-type fluctuations in $A$Fe${}_2$As${}_2$ ($A$ = K, Rb, Cs) superconductors probed by ${}^{75}$As NMR spectroscopy
• Doping evolution of the superconducting gap structure in heavily hole-doped Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$: heat transport study
• Spectroscopic studies of the superconducting gap in the 12442 family of iron-based compounds
• Possible superconducting fluctuation and pseudogap state above $T_c$ in CsFe${}_2$As${}_2$
• Vortex lattice and vortex bound states in CsFe${}_2$As${}_2$ investigated by scanning tunneling microscopy/spectroscopy
• Two-Dimensional Phase-Fluctuating Superconductivity in Bulk-Crystalline NdO${}_{0.5}$F${}_{0.5}$BiS${}_2$