School of Physics M013, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia.
J Phys Condens Matter. 2011 Mar 16;23(10):105901. doi: 10.1088/0953-8984/23/10/105901. Epub 2011 Feb 18.
We present a theory for surface polaritons on ferroelectric-antiferromagnetic materials with canted spin structure. A small uniform canted moment is allowed, resulting in a weak ferromagnetism directed in the plane parallel to the surface. Surface and bulk polariton modes for a semi-infinite film are calculated for the case of transverse electric (TE) and transverse magnetic (TM) polarization. Example results are presented using parameters appropriate for BaMnF(4). We find that the surface modes are non-reciprocal for the TE polarization due to the magnetoelectric interaction, and the non-reciprocity can be controlled by an applied electric field. Example results for attenuated total reflection (ATR) are calculated. The magnetoelectric interaction also gives rise to 'leaky' surface modes in the case of TM polarization. These are pseudo-surface waves that exist in the pass band, and dissipate energy into the bulk of the material. We show that these pseudo-surface mode frequencies and properties can be modified by temperature and the application of external electric or magnetic fields.
我们提出了一种关于具有倾斜自旋结构的铁电-反铁磁材料表面极化激元的理论。允许存在小的均匀倾斜矩，导致在平行于表面的平面内指向的弱铁磁性。对于横电 (TE) 和横磁 (TM) 极化，计算了半无限薄膜的表面和体极化激元模式。使用适合 BaMnF(4) 的参数给出了示例结果。我们发现，由于磁电相互作用，TE 极化的表面模式是非互易的，并且可以通过施加电场来控制非互易性。计算了衰减全反射 (ATR) 的示例结果。在 TM 极化的情况下，磁电相互作用也会导致“泄漏”表面模式。这些是存在于通带中的赝表面波，并将能量耗散到材料的体部。我们表明，这些赝表面模式的频率和性质可以通过温度以及施加的外电场或磁场来修改。
