Effect of Co-Ga paired substitution on superconductivity in YBa2Cu3O7-d

TL;DR

This study investigates how paired substitution of magnetic Co and non-magnetic Ga ions at the Cu site affects the superconducting properties of YBa2Cu3O7-d, revealing changes in transition temperature, oxygen content, and orthorhombicity.

Contribution

It provides new insights into the effects of magnetic and non-magnetic paired dopants on superconductivity in Y-123, focusing on the interplay of dopant valency and hole filling mechanisms.

Findings

Variation in Tc with dopant concentration

Changes in oxygen content and hole concentration

Orthorhombicity variation with doping

Abstract

The effect of Co-Ga paired substitution on the superconducting properties of YBa2Cu3O7-d (Y-123) has been investigated by X-ray diffraction, ac susceptibility,dc resistivity and oxygen content measurements. We report in this paper the results of our studies on the paired substitution of a magnetic and non-magnetic ion at Cu site in Y-123, while keeping the total dopant concentration fixed. The simultaneous substitution of Co and Ga at Cu site shows variation in the transition temperature (Tc), oxygen content and hole concentration as a function of change in the balance of magnetic (Co) and non-magnetic (Ga) concentration. Orthorhombicity (D), given as (b-a)/a, also varies as a function of increasing dopant concentration. The variation in Tc due to Co-Ga substitution is discussed in the light of dopant valency and hole filling mechanism.