电荷媒介的磁电耦合:从铁电场效应到电荷序铁电体

Charge-mediated magnetoelectricity:from ferroelectric field effect to charge-ordering ferroelectrics

磁电耦合效应是百年铁电领域中新兴的科学话题和前沿难点.包含两种及以上铁性序的多铁性材料则是追求本征强磁电耦合的理想体系,其展现了丰富的物理性质,蕴含着很高的应用潜力.作为关联电子大家庭的一个分支,多铁性材料体系也涉及电荷、自旋、轨道,以及晶格多重自由度.但过往的磁电耦合研究对自旋与晶格自由度关注最多,却往往忽略了其中的电荷自由度.实际上,电荷自由度可以在磁电耦合中扮演重要的媒介作用.本文将介绍异质结中的铁电场效应和单相多铁性材料中的电荷序所涉及的磁电耦合物理机制,以及回顾作者近年来在此方向上的若干尝试,希望能为本领域的研究者提供一些参考.

Magnetoelectricity is an emerging topic and a frontier issue of the field of ferroelectricity.Multiferroics containing more than one ferroic order is an ideal system to pursuit intrinsic and robust magnetoelectric coupling,which holds rich physics and great potential applications.As a branch of the correlated electron family,multiferroic also has multiple degrees of freedom,including the charge,spin,orbital,and lattice.Among them,the charge degree of freedom has been mostly overlooked in the past researches and actually it may play an important role in magnetoelectricity.In this topical review,the charge-mediated magnetoelectricity is introduced,including the ferroelectric field effect in heterostructures and the charge ordering in single-phase multiferroics.The physical mechanisms will be revealed,together with several examples we given in recent years.We hope that this topical review can provide a reference for the researches in this vigorous filed.