Quantum critical quasiparticle scattering within the superconducting state of CeCoIn5

Abstract

The thermal conductivity kappa of the heavy-fermion metal CeCoIn5 was measured in the normal and superconducting states as a function of temperature T and magnetic field H, for a current and field parallel to the [100] direction. Inside the superconducting state, when the field is lower than the upper critical field Hc2, kappa/T is found to increase as T approaches absolute zero, just as in a metal and in contrast to the behavior of all known superconductors. This is due to unpaired electrons on part of the Fermi surface, which dominate the transport above a certain field. The evolution of kappa/T with field reveals that the electron-electron scattering (or transport mass m^*) of those unpaired electrons diverges as H approaches Hc2 from below, in the same way that it does in the normal state as H approaches Hc2 from above. This shows that the unpaired electrons sense the proximity of the field-tuned quantum critical point of CeCoIn5 at H^* = Hc2 even from inside the superconducting state. The fact that the quantum critical scattering of the unpaired electrons is much weaker than the average scattering of all electrons in the normal state reveals a k-space correlation between the strength of pairing and the strength of scattering, pointing to a common mechanism, presumably antiferromagnetic fluctuations.

revised version - to appear in Phys. Rev. Lett

References in corpus (13)

• High-temperature superconductivity in iron-based materials
• A Sharp Peak of the Zero-Temperature Penetration Depth at Optimal Composition in BaFe2(As1-xPx)2
• Visualizing Nodal Heavy Fermion Superconductivity in CeCoIn5
• Concepts relating magnetic interactions, intertwined electronic orders and strongly correlated superconductivity
• Unpaired Electrons in the Heavy-Fermion Superconductor CeCoIn_{5}
• Nonvanishing Energy Scales at the Quantum Critical Point of CeCoIn5
• The Origin of Anomalous Low-Temperature Downturns in the Thermal Conductivity of Cuprates
• Field-induced quantum critical route to a Fermi liquid in high-temperature superconductors
• Zero-field Quantum Critical Point in CeCoIn${}_5$
• Hybrid gap structure in the heavy-fermion superconductor CeIrIn${}_5$
• Gapless Fermi Surfaces in anisotropic multiband superconductors in magnetic field
• Strong pressure dependence of the magnetic penetration depth in single crystals of the heavy fermion superconductor CeCoIn5 studied by muon spin rotation
• Heat transport study of field-tuned quantum criticality in CeIrIn5

Cited by in corpus (6)

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• The strange metal Hall effect connects quantum criticality and superconductivity in an iron-based superconductor
• Interplay of the spin density wave and a possible Fulde-Ferrell-Larkin-Ovchinnikov state in $\mathrm{CeCoI}{\mathrm{n}}_5$ in rotating magnetic field
• A "hidden" transition in heavy fermion compound CeB${}_6$ at $T\sim$ 20 K?
• Sub-Phases in the Superconducting State of CeIrIn${}_5$ Revealed by Low Temperature $c$-axis Heat Transport