Large magnetoelectric effect in the polar magnet Sm2BaCuO5.

Polar magnets are a family of promising candidates for future magnetoelectric (ME) applications. In particular, the ME effect is recognized for its potential use in low-power electronic devices. However, searching for materials with a sufficiently strong ME effect remains the core issue. In this work, we present a systematic investigation on oxide compound Sm₂BaCuO₅, including the characterization on structural, magnetic, specific heat, dielectric, and pyroelectric behaviors. The intrinsic linear ME effect is revealed, and two successive antiferromagnetic phase transitions occurring at temperatures of T_N1 ∼ 5 K and T_N2 ∼ 23 K are found, respectively. While a magnetic field induced electric polarization emerges below T_N2 and this polarization increases with the magnetic field in an almost linear manner, another weak pyroelectric current peak is detected around T_N1. Furthermore, remarkable responses of both electric polarization to the magnetic field and magnetization to the electric field are demonstrated. It is suggested that the intriguing magnetic interactions play the core roles in generating the ferroelectricity and ME effect in this Sm₂BaCuO₅ compound. [ABSTRACT FROM AUTHOR]