In spin-driven ferroelectrics, often referred to as magnetoelectric (ME) multiferroics, a domain wall separates two magnetic as well as ferroelectric domains. Therefore, it is expected that the control of such an ME domain wall could result in a large ME effect. Here, we show that the direction of a slanted magnetic field controls whether the electric polarization $\left(\mathit{P}\right)$ rotates by $+90$ or $-90°$ upon the $\mathit{P}$-flop transition in a prototypical spiral magnetic ferroelectric ${\text{TbMnO}}_3$. This behavior is discussed in terms of the domain-wall energy of a spiral magnet in a slanted magnetic field.

• Received 18 September 2008

DOI:https://doi.org/10.1103/PhysRevB.80.020402