平面波展开法计算二维磁振子晶体带结构

Band-structure calculations of two-dimesional magnonic crystals with plane-wave expansion method

磁振子晶体是光子晶体或声子晶体在磁性材料领域内的替代品,是近来的一个研究热点.本文提出了磁振子晶体领域内的一种平面波展开法,其较传统的平面波展开法能节约一半以上的计算时间.采用此方法,数值计算了由Fe/EuO二种铁磁材料构成的二维磁振子晶体带结构.数值计算结果表明,在一定的体积填充率下,有自旋波带隙的出现;影响磁振子晶体带隙结构形成的主要因素是有效场中的交换作用场,其他作用场的影响相对很小.

Recently, magnonic crystals which are the magnetic counterparts of photonic crystals or phononic crystals are growing into a hot area of research. In this paper, a plane-wave expansion method in the field of magnonic crystals is proposed. By using this method, band structures of two-dimensional magnonic crystals composed of ferromagnetic materials Fe and EuO are calculated. The numerical results show that the spin-wave gaps will be generated under a definite filling fraction ratio, and the effect of exchange field on the band structure is larger than that of other field in the effective field.