Negative Chemical Pressure Effect on the Superconductivity and Charge Density Wave of Cu0.5Ir1–x Zr x Te2

This study demonstrates the design and synthesis of the Cu0.5Ir1–x Zr x Te2 (0 ≤ x ≤ 0.15) 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 find evidence that the charge density wave (CDW)-like order is immediately quenched by subtle Zr substitution for Ir and a classical dome-shape T c(x) that peaked at 2.80 K can be observed. The optimal Cu0.5Ir0.95Zr0.05Te2 compound is a Bardeen–Cooper–Schrieffer (BCS)-type superconductor and exhibits type-II superconductivity (SC). However, high Zr concentrations (x > 0.1) can provoke disorders, inducing the reappearance of CDW orders. The present study shows that the Cu0.5Ir1–x Zr x Te2 (0 ≤ x ≤ 0.15) system may provide a new platform for further understanding multiple electronic orders in transition-metal dichalcogenides.