Physique Théorique des Matériaux, Université de Liège, B-4000 Sart-Tilman, Belgium.
Centro de Investigación y Estudios Avanzados del IPN, MX-76230 Querétaro, Mexico.
Phys Rev Lett. 2016 Mar 18;116(11):117202. doi: 10.1103/PhysRevLett.116.117202. Epub 2016 Mar 14.
In this study we show from first principles calculations the possibility to induce multiferroic and magnetoelectric functional properties in the Pnma NaMnF_{3} fluoroperovskite by means of epitaxial strain engineering. Surprisingly, we found a very strong nonlinear polarization-strain coupling that drives an atypical amplification of the ferroelectric polarization for either compression or expansion of the cell. This property is associated with a noncollinear antiferromagnetic ordering, which induces a weak ferromagnetism phase and makes the strained NaMnF_{3} fluoroperovskite multiferroic. The magnetoelectric response was calculated and it was found to be composed of linear and nonlinear components with amplitudes similar to the ones of Cr_{2}O_{3}. These findings show that it is possible to move the fluoride family toward functional applications with unique responses.
在这项研究中，我们通过第一性原理计算表明，通过外延应变工程有可能在 Pnma NaMnF_3 氟钙钛矿中诱导出多铁和磁电功能特性。令人惊讶的是，我们发现了一种非常强的非线性极化-应变耦合，它驱动了铁电极化的非典型放大，无论是对细胞的压缩还是扩张。这种性质与非共线反铁磁有序有关，它会导致弱铁磁相，并使应变 NaMnF_3 氟钙钛矿成为多铁性材料。计算了磁电响应，发现它由线性和非线性分量组成，幅度与 Cr_2O_3 的相似。这些发现表明，有可能使氟化物家族朝着具有独特响应的功能应用方向发展。
