Highlights

Researchers combined experiments and computer simulations to uncover why contractile asters, made of biopolymers, slow down in coalescence and can have liquid or solid traits. They identified the reasons for asters becoming solid and created new ways to form liquid-like asters. Additionally, other studies looked at how actin filaments affect the movements of these asters. This work helps fill in knowledge gaps about the behavior of these structures in living systems.

Researchers at UMN MRSEC have explored the self-assembly of ABC bottlebrush block terpolymers, which could lead to new material designs. Unlike traditional diblock bottlebrushes, these new structures showed interesting formations like core-shell cylinders and an unusual rectangular pattern. They found that by changing the molecular weight, they could achieve a variety of sizes. This work opens up exciting possibilities for creating materials with unique structures and sizes for uses in photonic crystals and metamaterials.

Recent research on oxide electrochemical transistors from the UMN MRSEC has significantly improved their performance, particularly in cycling endurance. A collaboration led to record durability in ion-gel transistors using La_0.5Sr_0.5CoO_3-d (LSCO), enhancing previous limits drastically. By applying operando FTIR spectroscopy, researchers gained insights into the factors affecting performance, such as humidity and device design. These advancements open up potential uses for LSCO in areas like thermal camouflage and thermoregulation.

Researchers developed active solids made of centimeter-scale building blocks that can move and adapt in different environments. These prototypes show unique elasticity, which allows them to change their movement patterns and navigate various terrains effectively, similar to complex robotic systems. This study highlights the potential of these materials to link robotics and material science and suggests new ways to control dynamic systems in nature and technology.

A recent study by Hojin Kim and Samantha Livermore shows that dense suspensions can be trained to respond differently to stress levels, similar to how living organisms train for better performance. By applying shear stress, these materials can develop “memories” that affect their mechanical properties, becoming either stiffer or softer with repeated impacts. This innovative approach suggests potential applications for materials that can adapt and change their viscosity or energy dissipation on demand.

Researchers have created a new cobalt-based metal-organic framework that shows potential for hosting a Kitaev spin liquid. This material features cobalt ions in a honeycomb arrangement, linked together by benzoquinone, which creates a special type of magnetic frustration. By adjusting the linkers' chemical composition, the strength of the magnetic interactions can be varied. While magnetization tests indicated antiferromagnetic interactions, no spin ordering was found at low temperatures, highlighting this framework's potential in exploring spin liquid physics.

Researchers have theoretically shown that distinct signs of Majorana excitations can be found in the Kitaev honeycomb model when a perpendicular magnetic field is applied. These unique features appear in what are called two-spin-flip excitations. The findings suggest that techniques like nonlinear THz spectroscopy could help detect these signatures in materials that are being studied as spin liquids. This work advances the understanding of quantum matter in these complex systems.

A recent study showcased how boron-vacancy centers in hexagonal boron nitride can be used for quantum sensing. These defects allow for the detection of weak magnetic fields through their spin-sensitive light emissions. The researchers demonstrated the capability to optically detect specific magnetic wave behaviors in materials like yttrium iron garnet. This work positions boron-vacancy centers as a flexible tool for exploring various magnetic phenomena in new material systems.

A new type of magnetoresistance called unidirectional magnetoresistance (UMR) has been discovered in a study that combines a topological semimetal (WTe₂) with a ferromagnetic semiconductor (Cr₂Ge₂Te₆). This phenomenon involves changes in resistance linked to magnetization reversal and spin interactions. The findings highlight how the unique properties of these materials can create distinct resistance states, which could be valuable for developing more advanced magnetic memory devices.

One of the research goals of UCSD MRSEC IRG2 included developing shape-shifting materials driven by asymmetric forces. In a recent effort, the MRSEC team demonstrated an ELM capable of shape-shifting driven by both a temperature stimulus and enzymatic mediated partial degradation of the composite material.