We review electric dipole active magnetic resonance and nonreciprocal directional dichroism in magnetoelectric multiferroic materials in terahertz and millimeter wave regions. Owing to dynamical magnetoelectric coupling generated by the spin-dependent electric polarization, magnetic resonance, which usually occurs owing to magnetic dipole transition, can be induced by the oscillating electric fields of electromagnetic wave. This electric dipole active magnetic resonance can be useful for microscopic investigations of magnetic excitation in unconventional spin systems. The magnetoelectric coupling also induces the nonreciprocal directional dichroism, which provides a novel functionality to materials as an optical diode, in teraheltz and microwave absorption by magnetic resonance. As examples, we describe the results of the high field ESR measurements of the triangular lattice antiferromagnet \(\hbox {CuFeO}_{\mathrm{2}}\) and the interacting quantum spin dimer systems \(\hbox {TlCuCl}_{\mathrm{3}}\) and \(\hbox {KCuCl}_{\mathrm{3}}\).

我们回顾了太赫兹和毫米波区域中的磁电多铁性材料中的电偶极子主动磁共振和不可逆方向二向色性。由于由自旋相关的极化产生的动态磁电耦合，通常由电磁偶极跃迁引起的磁共振可以由电磁波的振荡电场引起。这种电偶极子有源磁共振可以用于非常规自旋系统中磁激发的微观研究。磁电耦合还引起不可逆的方向二向色性，在太赫兹和通过磁共振吸收微波中，这为作为光电二极管的材料提供了新颖的功能。举例来说，\（\ hbox {CuFeO} _ {\ mathrm {2}} \）和相互作用的量子自旋二聚体系统\（\ hbox {TlCuCl} _ {\ mathrm {3}} \）和\（\ hbox {KCuCl} _ {\ mathrm {3}} \）。