Negative Chemical Pressure Effect on Superconductivity and Charge Density Wave of Cu0.5Ir1-xZrxTe2

TL;DR

This paper investigates how substituting Zr for Ir in Cu0.5IrTe2 induces negative chemical pressure, suppresses charge density wave order, and enhances superconductivity, revealing new insights into electronic orders in transition metal dichalcogenides.

Contribution

It introduces a new Cu0.5Ir1-xZrxTe2 system demonstrating how negative chemical pressure affects superconductivity and charge density waves, providing a platform for studying electronic orders.

Findings

Zr substitution expands cell parameters indicating negative chemical pressure

Charge density wave order is suppressed by Zr doping

Optimal doping yields a BCS-type superconductor with Tc of 2.80 K

Abstract

This study demonstrates the design and synthesis of Cu0.5Ir1-xZrxTe2 system by partial substitution of Ir with Zr acting as a negative chemical pressure. With the doping of Zr, the cell parameters significantly expand, signifying an effective negative chemical pressure. The experimental results found evidence that the charge density wave (CDW)-like order is immediately quenched by subtle Zr substitution for Ir and a classical dome-shape Tc(x) that peaked at 2.80 K can be observed. The optimal Cu0.5Ir0.95Zr0.05Te2 compound is a BCS-type superconductor and exhibits type-II SC. However, high Zr concentration can provoke disorder, inducing the reappearance of CDW order. The present study shows that the Cu0.5Ir1-xZrxTe2 system may provide a new platform for further understanding of multiple electronic orders in transition metal dichalcogenides.