“结构与性能关系”是材料科学与工程的中心范式。随着材料研究的发展,人们对材料微观结构与性能的认识已深入到原子与电子层次。不仅低维材料直接在原子尺度进行设计与调控,即使是传统的工程材料,其合成制备、宏观性能、服役行为也往往需要追溯到原子尺度的微观结构。
我们长期从事电子显微学与材料科学研究,主要在原子尺度研究材料的晶体结构与缺陷、电子结构与磁结构,并开展稀土永磁材料与工艺研究。发明了自适应传播因子叠层成像、局域轨道叠层成像、局域轨道三维重构等方法,将显微成像的信息极限推进到了14皮米,实现了原子分辨的磁成像、低剂量亚埃分辨成像、金属中单个间隙轻原子的显微成像。
目前的主要方向包括:
1、电子显微学方法:电子叠层成像算法;原子分辨三维重构算法;电子衍射与成像计算。
2、材料的微观结构:晶体结构与缺陷;电子结构与磁结构。
3、新材料与新工艺:稀土永磁材料。
近期论文:
l R. Yu, H.Z. Sha, J.Z. Cui, W.F. Yang, Introduction to electron ptychography for materials scientists, Microstructures, 4, 2024056 (2024).
l L.Z. Mao, J.Z. Cui, R. Yu, 3D reconstruction of a million atoms by multiple-section local-orbital tomography, Science Bulletin, 70, 64 (2025).
l H.Z. Sha, Y.X. Zhang, Y.P. Ma, W. Li, W.F. Yang, J.Z. Cui, Q. Li, H.B. Huang, R. Yu, Polar vortex hidden in twisted bilayers of paraelectric SrTiO3, Nature Communications, 15, 10915 (2024).
l H.Z. Sha, J.Z. Cui, W.F. Yang, R. Yu, Information limit of 15 picometers achieved with bright-field ptychography, Physical Review B, 110, L060104 (2024).
l Z.W. Wu, Y.X. Zhang, W. Zhu, T.Q. Zhang, R. Yu, Grain boundary phases in (Ga, Cu)-doped Nd-Fe-B sintered magnet, Acta Materialia, 278, 120196 (2024).
l W.F. Yang, H.Z. Sha, J.Z. Cui, L.Z. Mao, R. Yu, Local-orbital ptychography for ultrahigh-resolution imaging, Nature Nanotechnology, 19, 612 (2024).
l J.B. Zhang et al., A correlated ferromagnetic polar metal by design, Nature Materials, 23, 912 (2024).
l Z.W. Wu, Y.J. Yu, T.Q. Zhang, R. Yu, Microstructure analysis of Ti-doped sintered Nd-Fe-B magnets, Acta Materialia, 265, 119511 (2024).
l J.Z. Cui, H.Z. Sha, W.F. Yang, R. Yu, Antiferromagnetic imaging via ptychographic phase retrieval, Science Bulletin, 69, 466 (2024).
l H.Z. Sha, J.Z. Cui, J.L. Li, Y.X. Zhang, W.F. Yang, Y.D. Li, R. Yu, Ptychographic measurements of varying size and shape along zeolite channels, Science Advances, 9, eadf1151 (2023).
l C. Liu, J.Z. Cui, Z.Y. Cheng, B.Z. Zhang, S.Y. Zhang, J. Ding, R. Yu, E. Ma, Direct observation of oxygen atoms taking tetrahedral interstitial sites in medium-entropy body-centered-cubic solutions, Advanced Materials, 2209941 (2023).
l H.Z. Sha, Y.P. Ma, G.P. Cao, J.Z. Cui, W.F. Yang, Q. Li, R. Yu, Sub-nanometer-scale mapping of crystal orientation and depth-dependent structure of dislocation cores in SrTiO3, Nature Communications, 14, 162 (2023).
l Y.H. Liang et al., Field-free spin-orbit switching of perpendicular magnetization enabled by dislocation induced in-plane symmetry breaking, Nature Communications, 14, 5458 (2023).
l H.Z. Sha, J.Z. Cui, R. Yu, Deep sub-angstrom resolution imaging by electron ptychography with misorientation correction, Science Advances, 8, eabn2275 (2022).
l T.Q. Zhang, W.D. Xing, F.G. Chen, L.T. Zhang, R. Yu, Improvement of coercivity and its thermal stability of hot-deformed Nd-Fe-B magnets processed by Tb70Cu30 doping and subsequent Nd85Cu15 diffusion, Acta Materialia, 220, 117296 (2021).