Giant magnetic in-plane anisotropy and competing instabilities in Na3Co2SbO6
Xintong Li, Yuchen Gu, Yue Chen, V. Ovidiu Garlea, Kazuki Iida, Kazuya Kamazawa, Yangmu Li, Guochu Deng, Qian Xiao, Xiquan Zheng, Zirong Ye, Yingying Peng, I. A… 展开作者
Xintong Li, Yuchen Gu, Yue Chen, V. Ovidiu Garlea, Kazuki Iida, Kazuya Kamazawa, Yangmu Li, Guochu Deng, Qian Xiao, Xiquan Zheng, Zirong Ye, Yingying Peng, I. A. Zaliznyak, J. M. Tranquada, Yuan Li
备注：
19 pages, 15 figures, 1 animation; to appear in Phys. Rev. X
We report magnetometry data obtained on twin-free single crystals of Na3Co2SbO6, which is considered a candidate material for realizing the Kitaev honeycomb model for quantum spin liquids. Contrary to a common belief that such materials can be modeled with the symmetries of an ideal honeycomb lattice, our data reveal a pronounced two-fold symmetry and in-plane anisotropy of over 200%, despite the honeycomb layer's tiny orthorhombic distortion of less than 0.2%. We further use magnetic neutron diffraction to elucidate a rich variety of field-induced phases observed in the magnetometry. These phases manifest themselves in the paramagnetic state as diffuse scattering signals associated with competing ferro- and antiferromagnetic instabilities, consistent with a theory that also predicts a quantum spin liquid phase nearby. Our results call for theoretical understanding of the observed in-plane anisotropy, and render Na3Co2SbO6 a promising ground for finding exotic quantum phases by targeted external tuning.
Competing instabilities of the extended Hubbard model on the triangular lattice: Truncated-unity functional renormalization group and application to moiré materials
Competing electronic instabilities of extended Hubbard models on the honeycomb lattice: A functional Renormalization Group calculation with high wavevector resolution
Competing instabilities, orbital ordering and splitting of band degeneracies from a parquet renormalization group analysis of a 4-pocket model for iron-based superconductors: application to FeSe
利用Parquet重整化群（RG）方法研究了铁基超导体全二维四口袋三轨道低能模型中的竞争不稳定性.我们推导并分析了耦合的RG流，它描述了低能费米子之间的所有物理允许的相互作用。尽管耦合的数量是大的，我们认为，只有两个稳定的固定轨迹的RG流和一个弱不稳定的固定轨迹与一个单一的不稳定方向。每个固定的轨迹在初始系统参数的空间中具有有限的吸引域。在稳定轨道上，要么只涉及$d_{xz}$和$d_{yz}$的相互作用，要么只涉及电子袋上的$d_{xy}$轨道分量占主导地位，而在弱不稳定轨道上，涉及电子袋上的$d_{xz}$（$d_{yz}$）和$d_{xy}$轨道状态的相互作用仍然相当。沿着两个稳定的固定轨道的行为已经在前面分析过[A. V. Chubukov，M. Khodas和R.M. Fernandes，arXiv：1602.05503].在这里，我们专注于沿弱不稳定轨迹的系统行为，并将结果应用到FeSe。我们发现，基于沿这条轨迹的不稳定性分析，在降低温度时的主导不稳定性是朝向{ \it三分量} d-波轨道π阶。两个分量是空穴袋和电子袋上的$d_{xz}$和$d_{yz}$轨道上的费米子密度之差，第三个分量是两个电子袋上的$d_{xy}$轨道密度之差。我们认为，这种顺序是一致的分裂带简并，观察到在最近的光电发射数据FeSe的A。Fedorov等人[arXiv：1606.03022]。
Topological states in pyrochlore iridates: long-range anisotropy strongly competing with spin-orbit interaction
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Competing lattice structures induced by Sn substitution in CsV$_3$Sb$_5$
Università di Parma（帕尔马大学）；Brown University（布朗大学）；Università di Bologna（博洛尼亚大学）；Istituto Officina dei Materiali, Consiglio Nazionale delle Ricerche（意大利国家研究委员会材料工坊研究所）；University of California Santa Barbara（加州大学圣塔芭芭拉分校）
Flat band driven competing charge and spin instabilities in the altermagnet CrSb
Donostia International Physics Center (DIPC)（多诺斯蒂亚国际物理中心）；Centro de Física de Materiales (CFM-MPC), CSIC-UPV/EHU（材料物理中心，西班牙国家研究委员会/巴斯克国立大学）；Fisika Aplikatua Saila, Gipuzkoako Ingeniaritza Eskola, University of the Basque Country (UPV/EHU)（应用物理系，吉普斯夸工程学院，巴斯克国立大学）；Department of Applied Physics, KTH Royal Institute of Technology（皇家理工学院应用物理系）；Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences（凝聚态物理北京实验室，中国科学院物理研究所）；Swiss-Norwegian BeamLines at European Synchrotron Radiation Facility（欧洲同步辐射装置瑞士-挪威光束线）；European Synchrotron Radiation Facility (ESRF)（欧洲同步辐射装置）；Département de Physique et Institut Quantique, Université de Sherbrooke（物理系与量子研究所，舍布鲁克大学）
Anisotropic Moiré Fractional Chern Insulators and Their Phase Transitions
Nanyang Technological University（南洋理工大学）；Hong Kong University of Science and Technology（香港科技大学）；Center for Theoretical Condensed Matter Physics, The Hong Kong University of Science and Technology（香港科技大学理论凝聚态物理中心）
