Effect of Mn substitution on the delicate balance between structure and properties of Gd1.4Ce0.6Sr2RuCu2O10

TL;DR

This study investigates how substituting Mn for Ru in Gd1.4Ce0.6Sr2RuCu2O10 affects its structure, magnetism, and superconductivity, revealing structural changes and suppression of superconductivity even at low Mn levels.

Contribution

It provides new insights into the effects of Mn substitution on the structural and magnetic properties of Ruthenocuprates, especially regarding the suppression of superconductivity.

Findings

Mn substitution causes structural changes and lattice parameter variation.

Superconductivity is suppressed even at 1 mole% Mn substitution.

Magnetic transition temperature decreases with Mn substitution.

Abstract

Some new members of a Ruthenocuprate (2212) series have been synthesized by Mn substitution for Ru in Gd1.4Ce0.6Sr2RuCu2O10 . Characterisation by XRD phase analysis followed by Rietveld refinement has been carried out. IR spectroscopy studies and Rietveld refinements are consistent with substitution of Mn at Ru site. XRD studies indicate changes in structural features on substitution including a significant change in lattice parameter for a very low substitution level (1mole% of Ru). The pristine compound shows coexistence of superconductivity and magnetism. Four probe resistivity studies indicate a semiconductor like upturn in resistivity and absence of superconductivity even for Mn substitution levels as low as 1 mole%. a. c. susceptibility measurements show a progressive suppression of the magnetic transition temperature as well as a smearing of the magnetic transition as a function of Mn substitution. Possible reasons for absence of superconductivity have been discussed.