基于PbMg_(1/3)Nb_(2/3)O_3-PbTiO_3压电单晶的磁电复合薄膜材料研究进展

电子信息技术的迅速发展对磁电功能器件的微型化、智能化、多功能化以及灵敏度、可靠性、低功耗等都提出了更高的需求,传统的块体磁电功能材料已日渐不能满足上述需求,而层状磁电复合薄膜材料同时具有铁电性、铁磁性和磁电耦合等多种特性,因此能满足上述需求且有望应用于新一代磁电功能器件.层状磁电复合材料不仅具有非常丰富的物理现象和效应,而且在弱磁探测器、多态存储器、电写磁读存储器、电场可调低功耗滤波器、移相器、天线等微波器件中也具有广阔的应用前景,因而受到材料科学家和物理学家广泛的关注和研究.在层状磁电复合材料中,功能薄膜/铁电单晶异质结因其制备简单、结构设计和材料选择灵活以及电场调控方便和有效,最近十余年引起了越来越多的研究人员的兴趣.目前,以具有优异铁电和压电性能的(1-x)PbMg_(1/3)Nb_(2/3)O_3-PbTiO_3(PMN-PT)单晶作为衬底,构建功能薄膜/PMN-PT异质结已成为国内外多铁性复合薄膜材料研究领域的重要方向之一.相比于其他国家,我国科学家无论在发表的文章数量还是在文章被引用次数方面都处于领先地位,表明我国在功能薄膜/PMN-PT单晶异质结方面的研究卓有成效.迄今为止,研究人员已构建了锰氧化合物/PMN-PT、铁氧体/PMN-PT、铁磁金属/PMN-PT、稀磁半导体/PMN-PT、发光材料/PMN-PT、二维材料/PMN-PT、多层薄膜/PMN-PT、超导薄膜/PMN-PT等多种类型的异质结,在理论研究和实验方面都取得了丰富的研究成果.本文对基于PMN-PT压电单晶的磁电复合薄膜材料的研究进展进行了总结:简要介绍了与功能薄膜/PMN-PT异质结相关的研究论文发表现状;介绍了PMN-PT单晶在准同型相界附近的相图和应变特性;按照功能薄膜材料所属的体系对异质结进行了分类,并选取部分代表性的研究成果,介绍了材料的磁电性能和内涵的物理机制;最后就目前有待解决的问题和未来可能的应用方向进行了总结和展望.

Progresses of magnetoelectric composite films based on PbMg1/3Nb2/3O3-PbTiO3 single-crystal substrates

Owing to the rapid development of microelectronic technology,higher requirements are raised for miniaturization, intellectualization,sensitivity,reliability,low-power consumption and versatile functions of electromagnetic functional devices,but conventional block magnetic or electrical functional materials cannot meet those requirements mentioned above any longer.Layered magnetoelectric composites,by contrast,have ferroelectric,ferromagnetic and magnetoelectric properties,so they are possible to satisfy these demands above and be applied to the next-generation magnetoelectric functional devices.Layered magnetoelectric composites not only have rich physical phenomena and effects,but also possess broad application prospects in weak magnetic field detectors,multi-state memories,electric-write/magnetic-read memories,electrically tunable filters,phase shifters,antennas,etc,which have attracted extensive attention of material scientists and physicists.Among layered magnetoelectric composites,the "functional thin film/ferroelectric single crystal" heterostructures have aroused increasingly interest due to their simple preparation method,flexible structural design,effective electric field control and low power consumption.Currently,because of the excellent ferroelectric and piezoelectric properties of the (1 -x) PbMg_1/3Nb_2/3O_3-xPbTiO₃(PMN-PT) single crystal,the functional thin film/PMN-PT single crystal heterostructure has become one of the hot research topics in the multiferroic composite thin film material field.On this research topic,Chinese scientists have made their own significant contributions to the research of functional thin film/PMN-PT single crystal heterojunction.So far,researchers have built multiple types of thin film/PMN-PT heterostructures,such as manganese oxide/PMN-PT,ferrite/PMN-PT,ferromagnetic metal/PMN-PT,dilute magnetic semiconductor/PMN-PT,luminescent material/PMN-PT,two-dimensional material/PMN-PT,multi-layer film/PMN-PT,superconductive material/PMN-PT,etc.,and they have made great achievements in both theoretical and experimental studies.In this review,we summarize the research progress of magnetoelectric composite thin films based on PMN-PT single crystal substrates in the last decade.We first briefly describe the current status of articles related to functional film/PMN-PT heterostructures.Then we introduce the phase diagram and electric-field-induced strain properties of the PMN-PT single crystal around the morphotropic phase boundary.We also classify the heterostructures according to different categories of functional thin film materials and discuss the representative research findings of each category in the past few years.Our discussion focuses on the magnetoelectric properties of materials and the intrinsic physical mechanism.Finally,we also discuss the scientific problems to be solved and predict the possible application directions in the future.