Giant dielectric permittivity and magnetocapacitance inLa0.875Sr0.125MnO3single crystals

Abstract

We report the observation of extremely high dielectric permittivity exceeding 10 9 and magnetocapacitance of the order of 10 4 % in La 0.875 Sr 0.125 MnO 3 single crystal. This phenomenon is observed below 270 K, and it exhibits a history dependence. These effects may be the consequence of strong competition and interplay among the charge, orbital, and spin degrees of freedom, resulting in nanoscale charge and spin dynamic inhomogeneities in the prepercolation regime of the phase segregation.

Colossal magnetodielectric effect caused by magnetoelectric effect under low magnetic field

“…And the distinct change in the dielectric constant commonly occurs near the magnetic phase transition under external magnetic field (Kimura et al 2003;Prellier et al 2005), similar to the colossal magnetoresistance (Weber et al 2006). The dielectric anomalies near the phase transition resulted from strong competition and interplay among the charge, orbital and spin degrees of freedom (Mamin et al 2007). The MD effect is percentage value of several decades, and is much higher near the insulator-metal transition (Rairigh et al 2007) or incommensurate-commensurate transition (Kimura et al 2003).…”

“…Recently, multiferroic materials have attracted much interest for their coexistence of ferroelectricity, ferromagnetism and ferroelasticity (Kimura et al 2003;Wang et al 2003;Hur et al 2004;Spaldin and Fiebig 2005;Eerenstein et al 2006;Weber et al 2006;Mamin et al 2007). The coupling between ferroelectric and ferromagnetic orders can produce some new effects, such as magnetoelectric (ME) and magnetodielectric (MD) effects.…”

“…MD = ε ( f ) /ε (0, f )×100% = ε (H, f ) − ε (0, f ) /ε (0, f )× 100%, where ε(H , f ) and ε(0, f ) are the dielectric constants of the multiferroic materials at frequency f in and out of the external magnetic field, respectively. The MD effects have been studied mainly on single phases, which show dielectric change under an external magnetic field (Kimura et al 2003;Hur et al 2004;Lorenz et al 2004;Weber et al 2006;Mamin et al 2007). The possibility of tuning the dielectric constant by external magnetic field open perspectives for the basic understanding of the multiferroic materials and for the design of devices.…”

“…The MD effect is percentage value of several decades, and is much higher near the insulator-metal transition (Rairigh et al 2007) or incommensurate-commensurate transition (Kimura et al 2003). But the magnetic field needed for producing the MD effect is commonly as high as several teslas (Kimura et al 2003;Hur et al 2004;Lorenz et al 2004;Weber et al 2006;Mamin et al 2007;Rairigh et al 2007). Alternatively, composites have stimulated much scientific and technological interest because the multiferroic properties are easily obtained by combining the individual ferroic phases.…”

Magnetoelectric effects on ferromagnetic and ferroelectric phase transitions in multiferroic materials

“…Large MDE effects were observed in GdFeO 3 , GaFeO 3 and TbMnO 3 resulting from the shift of dielectric peak under a magnetic field [8,9]. The dielectric anomalies near the phase transition result from the strong competition and interplay among the charge, orbital and spin degrees of freedom [10]. However, the natural MDE materials in single phases are known to be extremely rare http://dx.doi.org/10.1016/j.actamat.2014.05.038 1359-6454/Ó 2014 Acta Materialia Inc.…”