CoCr $_2$ O $_4$的多铁性是由于锥形自旋-螺旋磁有序的出现引起了电极化的强度。磁性基态具有复杂的尺寸依赖性行为，当达到临界颗粒尺寸时其崩溃。在这里，磁相稳定性的CoCr $_2$ O $_4$在3.6 - 14.0 nm的尺寸范围内的详细介绍了使用结合的中子衍射与XYZ极化分析和宏观磁化强度测量。我们建立了形成自旋螺旋和亚铁磁结构的临界相干畴尺寸，并揭示了无公度自旋螺旋矢量随颗粒尺寸的演化。我们进一步证实了纳米晶CoCr $_2$ O $_4$在自旋螺旋相中存在铁电极化。
英文摘要：
The multiferroic behavior of CoCr$_2$O$_4$ results from the appearance of conical spin-spiral magnetic ordering, which induces electric polarization. The magnetic ground state has a complex size dependent behavior, which collapses when reaching a critical particle size. Here, the magnetic phase stability of CoCr$_2$O$_4$ in the size range of 3.6 - 14.0 nm is presented in detail using the combination of neutron diffraction with XYZ polarization analysis and macroscopic magnetization measurements. We establish critical coherent domain sizes for the formation of the spin spiral and ferrimagnetic structure and reveal the evolution of the incommensurate spin spiral vector with particle size. We further confirm the presence of ferroelectric polarization in the spin spiral phase for nanocrystalline CoCr$_2$O$_4$.
Altermagnetic superconducting diode effect from non-collinear compensated magnetism in Mn$_3$Pt
Hearne Institute of Theoretical Physics, Department of Physics & Astronomy, Louisiana State University（路易斯安那州立大学）；Department of Physics, Indian Institute of Technology Delhi（印度理工学院德里分校）；Institute for Theoretical Physics III, University of Stuttgart（斯图加特大学）
Max Planck Institute for the Physics of Complex Systems（马克斯·普朗克复杂系统物理研究所）；Max Planck Institute for Chemical Physics of Solids（马克斯·普朗克固体化学物理研究所）；Institute of Physics, Czech Academy of Sciences（捷克科学院物理研究所）
Intra-unit-cell resolved intertwining of multi-$Q$ charge and spin textures in an itinerant skyrmion magnet
RIKEN Center for Emergent Matter Science（理化学研究所物质结构科学研究中心）；Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), University of Tokyo（东京大学应用物理系及量子相电子研究中心）；Institute for Solid State Physics, University of Tokyo（东京大学固体物理研究所）；Research Center for Advanced Science and Technology, University of Tokyo（东京大学先进科学技术研究中心）
University of Michigan（密歇根大学）；ITMO University（ITMO大学）；The University of Texas at Dallas（德克萨斯大学达拉斯分校）；Georgia Institute of Technology（佐治亚理工学院）；University of Iceland（冰岛大学）
