Core Viewpoint - Dutch physicists from Leiden University have developed a remarkable metamaterial that can autonomously contract and expand without any external force, resembling a self-"breathing" mechanism, opening new avenues for smart reconfigurable materials and micro-robotics [1][2]. Group 1 - The research team has created a structure in the microscopic world that challenges traditional perceptions of matter, where movement is derived from the intricate connections between particles rather than the material itself [1]. - The metamaterial is constructed from tiny silica spheres assembled into carefully designed building blocks, with each structural unit being 1/10th the width of a human hair, arranged in a rhombic pattern to ensure mechanical stability and allow for free rotation [1]. - The final structure, named "cage lattice," showcases the team's ability to build increasingly complex architectures from basic units [1]. Group 2 - Under optical microscopy, these microstructures exhibit the ability to spontaneously contract and expand, driven by thermal energy that facilitates elegant folding and unfolding movements [2]. - The movement is coordinated, with one set of quadrilaterals rotating clockwise while adjacent sets rotate counterclockwise, creating a harmonious rhythm of contraction and expansion [2]. - The introduction of magnetic particles allows for control over this microscopic "dance," with the opening and closing of magnetic fields precisely regulating the structure's contraction and expansion, paving the way for real-world applications [2]. Group 3 - The team has established a theoretical framework describing the interaction between thermal motion and the metamaterial, with experimental results closely aligning with theoretical predictions [3]. - This self-"breathing" metamaterial is expected to lay the groundwork for applications in artificial muscles, adaptive optical devices, and micro-robots that can autonomously respond to environmental changes [3].