Evolution of Structural and Physical Properties of Sr3(Ru1-xMnx)2O7 with Mn Concentration

TL;DR

This study investigates how Mn doping affects the structural, electrical, and magnetic properties of Sr3(Ru1-xMnx)2O7 single crystals, revealing phase transitions and property tuning through chemical doping.

Contribution

It provides detailed insights into the structural and physical evolution of Sr3(Ru1-xMnx)2O7 with Mn concentration, including phase diagram construction and property correlations.

Findings

Mn doping causes unit-cell shrinkage and suppresses octahedral rotations.

Metallic to insulating transition occurs at a characteristic temperature T_MIT.

Physical properties can be tuned by varying Mn concentration.

Abstract

Layered ruthenates are prototype materials with strong structure-property correlations. We report the structural and physical properties of double-layered perovskite Sr3(Ru1-xMnx)2O7 single crystals with 0<=x<=0.7. Single crystal x-ray diffraction refinements reveal that Mn doping on the Ru site leads to the shrinkage of unit-cell volume and disappearance of (Ru/Mn)O6 octahedron rotation when x>0.16, while the crystal structure remains tetragonal. Correspondingly, the electric and magnetic properties change with x. The electrical resistivity reveals metallic character (d rho/d T>0) at high temperatures but insulating behavior (d rho/d T<0) below a characteristic temperature T_MIT. Interestingly, T_MIT is different from T_M, at which magnetic susceptibility reaches maximum. T_MIT monotonically increases with increasing x while T_M shows non-monotonic dependence with x. The difference between T_MIT and T_M (T_MIT>T_M) becomes larger when x>0.16. The constructed phase diagram consists of five distinct regions, demonstrating that the physical properties of such a system can easily be tuned by chemical doping.