Raman optical activity, long thought to require chiral molecules or magnetic order, has been demonstrated in an achiral, nonmagnetic crystal by researchers at Institute of Science Tokyo. The effect arises through ferroaxial order, a coordinated rotation of atoms within the lattice, and is detected using circularly polarized Raman spectroscopy. These findings show that optically inactive materials can also display chirality-like optical responses and expand the scope of optical techniques for discovering new materials.  

GaN-based vertical-cavity surface-emitting lasers (VCSELs) are promising for displays, sensing, and optical communication, but improving efficiency remains challenging. Researchers have now shown that “cavity tuning,” which controls resonance wavelength, strongly affects laser performance. By analyzing variations across a VCSEL wafer, the team identified optimal mirror loss conditions and extracted device parameters. Their approach achieved 26.4% wall plug efficiency, offering guidance for next-generation high-efficiency visible-light semiconductor lasers.

An international research collaboration, including OMU, IJS, NIST and AUT, has unveiled a robust metallic state in the molecular material ytterbium cesium fulleride (Yb₂CsC₆₀) that directly tests conventional theories of electron behavior. Normally, strong interactions between electrons are expected to suppress their movement and turn materials into insulators through a process called a Mott transition. However, Yb₂CsC₆₀ represents a case where metallicity survived, suggesting that the material’s electrons were continuing to move collectively, stabilized by a different mechanism. The discovery is of relevance to future research in fields such as superconductivity, quantum matter, and next-generation electronic technologies.

A research team in Japan has developed an efficient and minimally invasive cancer detection device that uses high-performance zinc oxide nanowires to selectively capture extracellular vesicles (EVs) from bodily fluids. Using this device, researchers successfully captured cancer-related EVs from the blood serum of ovarian cancer patients.