Magnetic order in Ce0.95Nd0.05CoIn5: the Q-phase at zero magnetic field

TL;DR

This study reveals an incommensurate magnetic order in Ce0.95Nd0.05CoIn5 below its superconducting transition, similar to the field-induced Q-phase in CeCoIn5, suggesting superconductivity facilitates this magnetic state through enhanced nesting.

Contribution

It demonstrates the existence of a zero-field magnetic order in Ce0.95Nd0.05CoIn5 with the same propagation vector as the Q-phase, linking superconductivity to magnetic order formation.

Findings

Incommensurate magnetic order observed below superconducting transition.

Propagation vector identical to field-induced Q-phase in CeCoIn5.

Superconductivity likely enhances nesting conditions for magnetic order.

Abstract

We report neutron scattering experiment results revealing the nature of the magnetic order occurring in the heavy fermion superconductor Ce0.95Nd0.05CoIn5, a case for which an antiferromagnetic state is stabilized at a temperature below the superconducting transition one. We evidence an incommensurate order and its propagation vector is found to be identical to that of the magnetic field induced antiferromagnetic order occurring in the stoichiometric superconductor CeCoIn5, the so-called Q-phase. The commonality between these two cases suggests that superconductivity is a requirement for the formation of this kind of magnetic order and the proposed mechanism is the enhancement of nesting condition by d-wave order parameter with nodes in the nesting area.