Zhendong Jin, Yangmu Li, Zhigang Hu, Biaoyan Hu, Yiran Liu, Kazuki Iida, Kazuya Kamazawa, M. B. Stone, A. I. Kolesnikov, D. L. Abernathy, Xiangyu Zhang, Haiyang… 展开作者
Zhendong Jin, Yangmu Li, Zhigang Hu, Biaoyan Hu, Yiran Liu, Kazuki Iida, Kazuya Kamazawa, M. B. Stone, A. I. Kolesnikov, D. L. Abernathy, Xiangyu Zhang, Haiyang Chen, Yandong Wang, Chen Fang, Biao Wu, I. A. Zaliznyak, J. M. Tranquada, Yuan Li
备注：
27 pages, 27 figures including supplemental; comments are welcome
A large body of knowledge about magnetism is attained from models of interacting spins, which usually reside on magnetic ions. Proposals beyond the ionic picture are uncommon and seldom verified by direct observations in conjunction with microscopic theory. Here, using inelastic neutron scattering to study the itinerant near-ferromagnet MnSi, we find that the system's fundamental magnetic units are interconnected, extended molecular orbitals consisting of three Mn atoms each, rather than individual Mn atoms. This result is further corroborated by magnetic Wannier orbitals obtained by ab initio calculations. It contrasts the ionic picture with a concrete example, and presents a novel regime of the spin waves where the wavelength is comparable to the spatial extent of the molecular orbitals. Our discovery brings important insights into not only the magnetism of MnSi, but also a broad range of magnetic quantum materials where structural symmetry, electron itinerancy and correlations act in concert.
Spectroscopic signatures of molecular orbitals on a honeycomb lattice
最近已经表明，形成类苯分子轨道的趋势是具有蜂窝晶格的$4d$和$5d$过渡金属氧化物的共同特征。这种趋势与其他相互作用，如自旋轨道耦合和哈伯德相关性竞争，并可以部分或完全抑制。在计算中，SrRu $_{2}$ O $_{6}$给出了迄今为止最清晰的形成良好的分子轨道，然而，支持或反对这一命题的直接实验证据一直缺失。在本文中，我们表明，结合光电子能谱和光学研究可以用来确定分子轨道在SrRu $_{2}$ O $_{6}$。对称性驱动的电子选择规则抑制了某些分子轨道之间的光学跃迁，而光电发射和逆光电发射测量对它们不敏感。比较光电子能谱和光导谱，人们应该能够观察到分子轨道的清晰特征。
Three-site transition-metal clusters: going from localized electrons to molecular orbitals
最近合成的一系列具有过渡金属三聚体的同构化合物Ba $_4$ Nb TM $_3$ O $_{12}$（TM = Mn、Rh和Ir）具有共面几何构型，使得有可能研究从$3d$到$5d$过渡金属离子的分子轨道（MO）形成的趋势。我们的$ab$ $initio$计算的电子和磁性描述的实验结果，并证明逐步过渡的本地化的电子Mn的图片的MO图片Rh，特别是Ir。我们还表明，经常使用的标准，根据该金属-金属的距离在一个化合物短于在各自的金属总是给MO，可能会打破在某些情况下。
Molecular-Orbital Degeneracy Lifting and Suppression of a Flat-Band Metal in a Tetrahedral Cluster System NbSeI
Institute for Solid State Physics, the University of Tokyo（东京大学固体物理研究所）；Graduate School of Environmental, Life, Natural Science and Technology, Okayama University（冈山大学环境生命自然科技研究科）；Department of Physics, Nagoya University（名古屋大学物理学系）；Department of Advanced Materials Science, the University of Tokyo（东京大学先进材料科学系）；Japan Synchrotron Radiation Research Institute (JASRI)（日本同步辐射研究所）
Eight-unit-cell electronic modulations in cuprates originating from local molecular orbitals
Tsinghua University（清华大学）；Institute of Physics, Chinese Academy of Sciences（中国科学院物理研究所）；New Cornerstone Science Laboratory（新基石科学实验室）；Hefei National Laboratory（合肥国家实验室）
Metallic state in the vicinity of molecular orbital crystallization in the d$^1$ thiospinel ZnTi$_2$S$_4$ prepared via a reductive ion-exchange reaction
Spectroscopic evidence for a molecular orbital Kondo insulator
University of California, Berkeley（加州大学伯克利分校）；Lawrence Berkeley National Laboratory（劳伦斯伯克利国家实验室）；Stanford University（斯坦福大学）；SLAC National Accelerator Laboratory（SLAC国家加速器实验室）；National Synchrotron Radiation Research Center（台湾国家同步辐射研究中心）；University of Washington（华盛顿大学）；National Institute of Standards and Technology (NIST)（美国国家标准与技术研究院）
