Electronic tuning and uniform superconductivity in CeCoIn5

TL;DR

This study investigates how electron and hole doping affect the magnetic phase diagram and superconductivity in CeCoIn5, revealing weak pair breaking effects and providing insights into the doping mechanisms through experiments and density functional theory.

Contribution

It demonstrates the reversible electronic tuning of the magnetic phase diagram and quantifies the weak pair breaking effects of non-magnetic dopants in CeCoIn5.

Findings

Weak pair breaking effects for non-magnetic dopants in d-wave superconductor

Hole dopants induce magnetic moments with less pair breaking than electron dopants

Similar effects of Pt and Sn doping suggest superconductivity is not confined to CeIn3 planes

Abstract

We report a globally reversible effect of electronic tuning on the magnetic phase diagram in CeCoIn_{5} driven by electron (Pt and Sn) and hole (Cd, Hg) doping. Consequently, we are able to extract the superconducting pair breaking component for hole and electron dopants with pressure and co-doping studies, respectively. We find that these nominally non-magnetic dopants have a remarkably weak pair breaking effect for a d-wave superconductor. The pair breaking is weaker for hole dopants, which induce magnetic moments, than for electron dopants. Furthermore, both Pt and Sn doping have a similar effect on superconductivity despite being on different dopant sites, arguing against the notion that superconductivity lives predominantly in the CeIn_{3} planes of these materials. In addition, we shed qualitative understanding on the doping dependence with density functional theory calculations.