In a paper published today in Nature Synthesis, a team from the lab of University of Chicago Pritzker School of Molecular Engineering (UChicago PME) and Chemistry Department Prof. Paul Alivisatos explores the role of cation exchange in one of chemistry and material science’s central challenges: How covalent materials undergo structural change at the nanoscale. This greater understanding of how materials transform could have applications for designing and building semiconductors, unraveling complex chemical processes or creating previously unimagined material architectures, for example, in this work, nanocubes of indium arsenide (InAs) and gallium arsenide (GaAs). The team applied a cellular automaton computational model to explore the science, building a clear, simple model for future researchers to envision these minute changes. They believe this is the first time a cellular automaton model has been applied to the cation exchange reactions of nanocrystals.

A compact fiber-based system has been developed to compress mid-infrared laser pulses to 187 femtoseconds using low input power. By integrating a holmium-doped ZBLAN photonic crystal fiber within a nonlinear optical loop mirror, the approach achieves high compression efficiency with minimal pedestal energy, offering a simplified route to ultrafast mid-IR sources for spectroscopy and biomedical imaging.

Light speckle fluctuations, a noninvasive proxy for cerebral blood flow index (CBFi), are quantified by diffuse correlation spectroscopy. However, this conventional technique provides marginal brain sensitivity for CBFi in adult humans. To improve the brain sensitivity, researchers have now optimized interferometric diffusing wave spectroscopy—a novel approach to quantify the fluctuations. They demonstrated pulsatile CBFi monitoring at 4–4.5 cm source-collector separation in adults with moderate pigmentation.

Rice University researchers Jianwei Huang and Ming Yi have developed a new capability, magnetoARPES, building on angle-resolved photoemission spectroscopy (ARPES) that allows researchers to study quantum behaviors they have been unable to resolve using ARPES alone. 

Breakthrough discovery provides new clues about how these celestial bodies - that push the known laws of physics to their limits - find each other.

POSTECH and Pukyong National University researchers develop a conductive bioglue that seamlessly integrates tissues and electronic devices in the fluid‑filled body.