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Abstract Mechanical metamaterials with phase-changing inclusions offer tunable properties that respond to external stimuli such as temperature and load. This study explores strategies for designing such materials through systematic finite element (FE) simulations. A representative two-phase system: phase-changing inclusions embedded in a soft polymer matrix, is modeled to investigate how geometry and material properties influence deformation. Key geometric parameters include inclusion orientation, offset distance, and spacing and key material parameters include matrix stiffness, inclusion stiffness, and nonlinear behavior. Also, of particular interest is a stress-induced edge waviness tuning mechanism: under compression, rotating inclusions can tune the morphology of the straight or wavy boundaries, which can be harnessed to modulate surface friction. To validate the modeling approach, multi-material prototypes are fabricated via 3D printing (Stratasys Connex 260), and uniaxial compression tests are performed with digital image correlation (DIC) to measure strain fields. This framework reveals how phase-changing materials such as low melting point alloys or shape memory materials can enhance functionality by enabling transitions between soft and stiff states or reversible shape changes. The results provide insights into the design of adaptive metamaterials with controllable mechanical responses, paving the way for future applications in robotics, wearable devices, and responsive surfaces. 

In magnetic pyrochlore materials, the interplay of spin-orbit coupling, electronic correlations, and geometrical frustration gives rise to exotic quantum phases, including topological semimetals and spin ice. While these phases have been observed in isolation, the interface-driven phenomena emerging from their interaction have never been realized previously. Here, we report on the discovery of interfacial electronic anisotropy and rotational symmetry breaking at a heterostructure consisting of the Weyl semimetal Eu₂Ir₂O₇and spin ice Dy₂Ti₂O₇. Subjected to magnetic fields, we unveil a sixfold anisotropic transport response that is theoretically accounted by a Kondo-coupled heterointerface, where the spin ice’s field-tuned magnetism induces electron scattering in the Weyl semimetal’s topological Fermi-arc states. Furthermore, at elevated magnetic fields, we reveal a twofold anisotropic response indicative of the emergence of a symmetry-broken many-body state. This discovery showcases the potential of pyrochlore frustrated magnet/topological semimetal heterostructures in search of emergent interfacial phenomena. 

Abstract Solomon rings, upholding the symbol of wisdom with profound historical roots, were widely used as decorations in ancient architecture and clothing. However, it was only recently discovered that such topological structures can be formed by self-organization in biological/chemical molecules, liquid crystals, etc. Here, we report the observation of polar Solomon rings in a ferroelectric nanocrystal, which consist of two intertwined vortices and are mathematically equivalent to a$${4}_{1}^{2}$$ $4_1^2$link in topology. By combining piezoresponse force microscopy observations and phase-field simulations, we demonstrate the reversible switching between polar Solomon rings and vertex textures by an electric field. The two types of topological polar textures exhibit distinct absorption of terahertz infrared waves, which can be exploited in infrared displays with a nanoscale resolution. Our study establishes, both experimentally and computationally, the existence and electrical manipulation of polar Solomon rings, a new form of topological polar structures that may provide a simple way for fast, robust, and high-resolution optoelectronic devices.