Direct Imaging of Nanostructured Magnetic Metalattices in 3D*

Nano-engineered magnetic materials are of great interest for tuning magnetic interactions and because of their potential applications for next-generation spintronic devices. Nanoscale 3D magnetization textures such as inverse nickel metallatices can be fabricated by infiltrating close-packed silica nanospheres with nickel. Such structures can support many distinct magnetic phases and topologies, leading to a new class of nanostructured magnetic metamaterials. Despite recent success in theoretical predicting and fabricating these materials, 3D characterization of their structure and properties remains very challenging due to the lack of suitable microscopy tools. We developed a new 3D nanoscale magnetic imaging capability that combines x-ray magnetic circular dichroism, ptychographic imaging, and vector tomography. Using this new magnetic vector ptycho-tomography method on a synchrotron beamline, we imaged a nickel magnetic metallatice sample to unveil the underluing structure and spin texture.