多铁薄膜中的自旋波电场调控机制及器件的研究

Spin wave refers to the collective excitation and propagation of magnetization in a material. Because of the remarkable advantages including the low energy loss, the high speed, and the rewritability, the spin wave is expected to be the ideal alternative for the charge current in the next generation information industry. However, for a practical application of the spin wave, issues, including efficient generation, modulation, and detection of a spin wave, should be solved firstly, among which efficient modulation of a spin wave is the key for the information operation in a spin-wave device. In previous works, we found that an external magnetic field can be used to control the transmission of a spin wave in an antiferromagnetic insulator. This result implies that propagation of a spin wave is governed by the orientation of the Neel vector in an antiferromagnetic system, which inspired this work. Here, we propose to systematically investigate the spin-wave propagation in multiferroic thin films with ferroelectric-antiferromagnetic couplings, in which the Neel vector can be controlled by an electric field. By using this well-known feature, we suppose to demonstrate the electric-field modulation of a spin wave and develop the first original device. This work can not only deepen the understanding of the spin wave propagation in an antiferromagnetic insulator system but also be a breakthrough of the next generation information process devices.

自旋波是磁性材料中磁矩的集体激发，以自旋波为信息载体的新型电子器件，因其低能耗、可重写、高频率等独特的优点，在新一代信息工业中有潜在的应用。而自旋波电子器件的实现，必须以解决自旋波的高效激发、调控以及探测等关键技术问题为前提。其中高效的自旋波调控是实现对自旋波器件进行信息读写的关键所在。申请人在反铁磁绝缘体中成功实现了磁场对自旋波的有效调控，揭示了反铁磁磁矩取向对自旋波传输效率的主导作用。以此为基础，本工作将把具有铁电-反铁磁耦合的多铁超薄膜引入自旋波研究领域，利用其中反铁磁磁矩取向的电场可控性实现电场对自旋波传输的调控。在理论上深入理解绝缘反铁磁体系中自旋波传输机制的基础上，设计并实现电控自旋波的原始功能器件。为以自旋波为核心的信息处理器件打开新的理论及技术途径。

以自旋流替代电流是下一代电子器件最具竞争力的发展方向，而高效的自旋流调控是其技术核心。本工作以实现自旋流的电场调控并构建原理器件为核心目标，对下一代自旋流信息存储及处理器件的核心技术进行探索。在项目执行期间，发表了高水平学术论文13篇，其中SCI收录12篇，中文核心1篇；申请国家发明专利3项；培养博士研究生3名，硕士研究生12名（毕业5名）。自主研发多场耦合自旋测试平台及无掩膜光刻系统等科研设备5台套，构建了材料开发、器件成型、性能测试的全链条自旋电子材料科研平台。在项目支持下对以反铁磁为代表的磁有序物质中的自旋传输效应进行了广泛而深入的研究，并在实验上实现了基于磁电耦合效应的电控自旋开关原型器件，为未来的自旋电子器件的开发储备了技术指引了方向。