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Abstract Two-dimensional (2D) van der Waals (vdW) magnets have sparked widespread attention due to their potential in spintronic applications as well as in fundamental physics. Ferromagnetic vdW compound Fe3GeTe2 (FGT) and its Ga variants have garnered significant interest due to their itinerant magnetism, correlated states, and high magnetic transition temperature. Experimental studies have demonstrated the tunability of FGT’s Curie temperature, T C , through adjustments in quintuple layer numbers (QL) and carrier concentrations, n. However, the underlying mechanism remains elusive. In this study, we employ molecular beam epitaxy (MBE) to synthesize 2D FGT films down to 1 QL with precise layer control, facilitating an exploration of the band structure and the evolution of itinerant carrier density. Angle-resolved photoemission spectroscopy (ARPES) reveals significant band structure changes at the ultra-thin limit, while first-principles calculations elucidate the band evolution from 1 QL to bulk, largely governed by interlayer coupling. Additionally, we find that n is intrinsically linked to the number of QL and temperature, with a critical value triggering the magnetic phase transition. Our findings underscore the pivotal role of band structure and itinerant electrons in governing magnetic phase transitions in such 2D vdW magnetic materials.

Amniotic band can cause a broad spectrum of anomalies ranging from simple band constrictions to major craniofacial and visceral defects. It can cause significant neonatal morbidity. Accurate diagnosis will help in the management of the present pregnancy and in counseling with regard to future pregnancies. Here we report three cases of amniotic band syndrome detected in the prenatal period.

Many challenges remain in the effort to realize the exceptional mechanical and electrical properties of carbon nanotubes in composite materials. Here, we report on highly electrically conductive and mechanically stiff composites of polymers and single-walled carbon nanotubes (SWNT). Conductive SWNT-based nanofoams (aerogels) are used as scaffolds to create polymer [poly(dimethylsiloxane)] composites. The resulting composites possess electrical conductivities over 1 S cm−1and exhibit an ∼300% increase in the elastic modulus with as little as 1 vol% nanotube content. [ABSTRACT FROM AUTHOR]

Low-density nanoporous solids have notoriously poor mechanical properties. Here, we show that light-ion irradiation can significantly improve the elastic modulus and hardness of low-density silica nanofoams (aerogels). Both elastic modulus and hardness saturate with ion fluence, and the saturation level increases with the ion stopping power. Such ion-beam stiffening is attributed to local material modification along ion tracks. [ABSTRACT FROM AUTHOR]

We present a general approach to prepare metal/aerogel nanocomposites via template directed atomic layer deposition (ALD). In particular, we used a Ru ALD process consisting of alternating exposures to bis(cyclopentadienyl)ruthenium (RuCp2) and air at 350?°C to deposit metallic Ru nanoparticles on the internal surfaces of carbon and silica aerogels. The technique does not affect the morphology of the aerogel template and offers excellent control over metal loading by simply adjusting the number of ALD cycles. We also discuss the limitations of our ALD approach and suggest ways to overcome these. [ABSTRACT FROM AUTHOR]