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Abstract Interest in high‐entropy inorganic compounds originates from their ability to stabilize cations and anions in local environments that rarely occur at standard temperature and pressure. This leads to new crystalline phases in many‐cation formulations with structures and properties that depart from conventional trends. The highest‐entropy homogeneous and random solid solution is a parent structure from which a continuum of lower‐entropy offspring can originate by adopting chemical and/or structural order. This report demonstrates how synthesis conditions, thermal history, and elastic and chemical boundary conditions conspire to regulate this process in Mg_0.2Co_0.2Ni_0.2Cu_0.2Zn_0.2O, during which coherent CuO nanotweeds and spinel nanocuboids evolve. We do so by combining structured synthesis routes, atomic‐resolution microscopy and spectroscopy, density functional theory, and a phase field modeling framework that accurately predicts the emergent structure and local chemistry. This establishes a framework to appreciate, understand, and predict the macrostate spectrum available to a high‐entropy system that is critical to rationalizing property engineering opportunities. 

For isotropic swimming particles driven by self-diffusiophoresis at zero Reynolds number (where particle velocity responds instantaneously to applied force), the diffusive timescale of emitted solute can produce an emergent quasi-inertial behavior. These particles can orbit in a central potential and reorient under second-order dynamics, not the first-order dynamics of classical zero-Reynolds motion. They are described by a simple effective model that embeds their history-dependent behavior as an effective inertia, this being the most primitive expression of memory. The system can be parameterized with dynamic quantities such as particle size and swimming speed, without detailed knowledge of the diffusiophoretic mechanism. Published by the American Physical Society2024 

Multiferroic materials host both ferroelectricity and magnetism, offering potential for magnetic memory and spin transistor applications. Here, we report a multiferroic chalcogenide semiconductor Cu_1−xMn_1+ySiTe₃(0.04 ≤x≤ 0.26; 0.03 ≤y≤ 0.15), which crystallizes in a polar monoclinic structure (Pmspace group). It exhibits a canted antiferromagnetic state below 35 kelvin, with magnetic hysteresis and remanent magnetization under 15 kelvin. We demonstrate multiferroicity and strong magnetoelectric coupling through magnetodielectric and magnetocurrent measurements. At 10 kelvin, the magnetically induced electric polarization reaches ~0.8 microcoulombs per square centimeter, comparable to the highest value in oxide multiferroics. We also observe possible room-temperature ferroelectricity. Given that multiferroicity is very rare among transition metal chalcogenides, our finding sets up a unique materials platform for designing multiferroic chalcogenides. 

A scalable platform to synthesize ultrathin heavy metals may enable high efficiency charge-to-spin conversion for next-generation spintronics. Here we report the synthesis of air-stable, epitaxially registered monolayer Pb underneath graphene on SiC (0001) by confinement heteroepitaxy (CHet). Diffraction, spectroscopy, and microscopy reveal CHet-based Pb intercalation predominantly exhibits a mottled hexagonal superstructure due to an ordered network of Frenkel-Kontorova-like domain walls. The system’s air stability enables ex-situ spin torque ferromagnetic resonance (ST-FMR) measurements that demonstrate charge-to-spin conversion in graphene/Pb/ferromagnet heterostructures with a 1.5× increase in the effective field ratio compared to control samples.