近几年对多铁性材料的研究热潮导致对多铁性 物理的深刻理解并成功探索可能的应用. 相继发现 一些新的多铁性材料以及观测到很强的铁电/磁性耦 合或调控效应, 一些物理新机制也被提出来解释多 铁性及其中的效应. 然而, 相比于研究工作取得的成 果, 所揭示的问题和挑战似乎更多. 我们进行一些初 步的归纳, 虽然未必全面, 却希望可以引发更广泛和 深入的实验和理论研究工作:
(1) 多铁性—— 铁电性和磁性共存机制问题. 虽 然目前发现了如上所述的几种机制来实现铁电性和 磁性在单相材料中共存, 但其中仍然存在很多问题, 尤其是在螺旋状自旋序导致的多铁性系统中还有很 多基本问题. 首先, 螺旋状自旋序导致铁电性的微观 机制还没得到真正的解决. DM 相互作用是否是最重
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机制. 日本东京大学Tokura教授参照庞磁电阻锰氧化
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