Composition and field tuned magnetism and superconductivity in Nd1-xCexCoIn5

TL;DR

This study investigates how alloying Nd with Ce in Nd1-xCexCoIn5 tunes the material from magnetic to superconducting states, revealing coexistence of magnetism and superconductivity and demonstrating reversible control via composition and magnetic field.

Contribution

It introduces a new alloy system where magnetic and superconducting phases coexist and can be reversibly tuned, providing insights into their interplay.

Findings

Magnetic order persists over a broad composition range.

Superconductivity coexists with spin-density wave order for 0.83 <= x <= 0.95.

Reversible tuning of phases achieved by adjusting Ce/Nd ratio and magnetic field.

Abstract

The Nd1-xCexCoIn5 alloys evolve from local moment magnetism (x = 0) to heavy fermion superconductivity (x =1). Magnetic order is observed over a broad range of x. For a substantial range of x (0.83 <= x <= 0.95) in the temperature - composition phase diagram we find that superconductivity may coexist with spin - density wave magnetic order at the Fermi surface. We show that a delicate balance betwen superconducting and magnetic instabilities can be reversibly tuned by both the Ce/Nd ratio and magnetic field, offering a new and unique model electronic system.