Switching of magnetic domains reveals evidence for spatially inhomogeneous superconductivity

TL;DR

This paper provides evidence for a spatially inhomogeneous p-wave Cooper pair-density wave in CeCoIn5, revealed by magnetic domain switching, linking SDW order with modulated superconductivity.

Contribution

It demonstrates the presence of a triplet p-wave PDW in CeCoIn5 and shows SDW domain switching with magnetic field changes, indicating spatially modulated superconductivity.

Findings

Switching of SDW domains by small magnetic field changes.

Evidence for a triplet p-wave Cooper pair-density wave.

Association of spatially modulated superconductivity with SDW order.

Abstract

The interplay of magnetic and charge fluctuations can lead to quantum phases with exceptional electronic properties. A case in point is magnetically-driven superconductivity, where magnetic correlations fundamentally affect the underlying symmetry and generate new physical properties. The superconducting wave-function in most known magnetic superconductors does not break translational symmetry. However, it has been predicted that modulated triplet p-wave superconductivity occurs in singlet d-wave superconductors with spin-density wave (SDW) order. Here we report evidence for the presence of a spatially inhomogeneous p-wave Cooper pair-density wave (PDW) in CeCoIn5. We show that the SDW domains can be switched completely by a tiny change of the magnetic field direction, which is naturally explained by the presence of triplet superconductivity. Further, the Q-phase emerges in a common magneto-superconducting quantum critical point. The Q-phase of CeCoIn5 thus represents an example where spatially modulated superconductivity is associated with SDW order.