Low-temperature specific heat for ferromagnetic and antiferromagnetic orders in CaRu1-xMnxO3

TL;DR

This study investigates the low-temperature specific heat of CaRu1-xMnxO3 to understand how d electrons influence ferromagnetic and antiferromagnetic orders, revealing their strong coupling with magnetic phenomena across different Mn concentrations.

Contribution

It provides new insights into the role of itinerant d electrons in magnetic order evolution in CaRu1-xMnxO3 through detailed specific heat measurements.

Findings

Gamma remains constant at low x, indicating stable electronic states.

Gamma decreases linearly with increasing x above 0.2, showing changing electronic contributions.

Specific heat follows a T^2 dependence at low temperatures.

Abstract

Low-temperature specific heat of CaRu1-xMnxO3 was measured to clarify the role of d electrons in ferromagnetic and antiferromagnetic orders observed above x=0.2. Specific heat divided by temperature C_p/T is found to roughly follow a T^2 function, and relatively large magnitudes of electronic specific heat coefficient gamma were obtained in wide x range. In particular, gamma is unchanged from the value at x=0 (84 mJ/K^2 mol) in the paramagnetic state for x<=0.1, but linearly reduced with increasing x above x= 0.2. These features of gamma strongly suggest that itinerant d electrons are tightly coupled with the evolution of magnetic orders in small and intermediate Mn concentrations.