Dipole glass and mixed ferroglass phase in SrTiO3 ceramics doped with manganese

TL;DR

This paper investigates the phase transitions in Mn-doped SrTiO3 ceramics, revealing dipole glass and ferroglass phases through theoretical analysis of dielectric properties and impurity concentrations.

Contribution

It provides a theoretical framework to understand impurity-induced phase transitions in SrTiO3, identifying dipole glass and ferroglass states based on Mn2+ doping levels.

Findings

Dipole glass phase at Mn concentration less than 0.03.

Ferroglass phase at Mn concentration between 0.03 and 0.15.

Theoretical analysis of dielectric permittivity and polarization behavior.

Abstract

Recently new incipient ferroelectrics with off-center ions SrTiO3 with Mn2+ substituted for Sr2+ was revealed (Tkach et. al PRB 73, 104113 (2006). Experimental investigation of Sr1-xMnxTiO3 properties, namely temperature, frequency and external electric field dependence of dielectric permittivity at different concentrations gave evidence about phase transitions induced by the impurities. However their nature was not found out up to now because of the absence of the theoretical analysis of the results. In this paper we performed such analysis by the theoretical description of the temperature of dielectric permittivity maxima dependence on Mn2+ concentration, the change of residual polarization with temperature, frequency and temperature dependence of the permittivity with Arrhenius and Vogel-Fulcher law at smaller and larger concentration respectively. The obtained results had shown that at x less than 0,03 and x between 0,15 and 0,03 the considered system Sr1-xMnxTiO3 is in dipole glass state and mixed ferroglass phase respectively.