Strong magnetoelastic effect on the magnetoelectric phenomena of TbMn$_{2}$O$_{5}$

TL;DR

This study investigates how magnetoelastic effects influence the magnetoelectric properties of TbMn₂O₅, revealing significant Tb spin and lattice interactions that affect electric polarization and magnetic responses.

Contribution

It provides new insights into the role of Tb magnetoelastic effects in the magnetoelectric behavior of TbMn₂O₅, supported by experimental correlations and an effective free energy model.

Findings

Magnetization increase causes asymmetric $oldsymbol{ ext{α}}( extbf{H})$ curves at low temperatures.

Linear relationships among electric polarization, magnetostriction, and magnetization squared.

Magnetoelastic effects significantly influence low-field magnetoelectric phenomena.

Abstract

Comparative studies of magnetoelectric susceptibility ($\alpha$), magnetization ($M$), and magnetostriction ($u$) in TbMn$_{2}$O$_{5}$ reveal that the increment of $M$ owing to the field-induced Tb$^{3+}$ spin alignment coins a field-asymmetric line shape in the $\alpha(H)$ curve, being conspicuous in a low temperature incommensurate phase but persistently subsisting in the entire ferroelectric phase. Correlations among electric polarization, $u$, and $M^{2}$ variation represent linear relationships, unambiguously showing the significant role of Tb magnetoelastic effects on the low field magnetoelectric phenomena of TbMn$_{2}$O$_{5}$. An effective free energy capturing the observed experimental features is also suggested.