Charged states on carbon nanotubes keep their twist
Peer-Reviewed Publication
Updates every hour. Last Updated: 8-Nov-2026 15:15 ET (8-Nov-2026 20:15 GMT/UTC)
Tokyo, Japan – Scientists from Tokyo Metropolitan University have discovered that charged states made of two electrons and a positively charged hole (or vice versa) on atomically thin rolls of carbon atoms have a structure-derived “handedness” in how they interact with light. While electron-hole pairs, or “excitons,” were known to keep the chirality of the underlying nanotube, the team showed that adding a charge to create “trions” does not change this property. Their work highlights new ways in which carbon nanotubes might be used in next-gen optoelectronic devices.
Researchers at Kyushu University have developed a smart packaging film that changes color and glows under UV light in response to compounds released as meat spoils. Made with milk-derived casein, modified anthocyanins, and a metal–organic framework, the film responds to volatile compounds released during spoilage. On refrigerated mutton, fluorescence appeared at around Day 6, and the optimized film also slowed spoilage, showing its potential for monitoring freshness and helping preserve food quality.
As artificial intelligence (AI) drives demand for faster data transfer, conventional silicon optical modulators face speed and energy-efficiency limitations, often requiring power-hungry electronic circuits. By designing electrical and optical structures together, researchers built signal equalization into a compact slow-light silicon modulator. The device achieved data rates of 180 Gb/s without digital signal processing equalization and 200 Gb/s using a low-complexity 11-tap digital equalizer, offering potential for high-capacity, energy-efficient optical connections in future AI data centers.
Deep beneath the Antarctic ice lies a telescope unlike any other—one that uses the ice itself to explore the universe in ways no conventional telescope can. The IceCube Neutrino Observatory (IceCube) is the world’s largest neutrino telescope, with 5,160 high-precision photodetectors embedded 1,450 to 2,450 meters beneath the South Pole. Since its completion in 2011, IceCube has opened a new window on the universe, detecting elusive neutrinos from some of the most energetic objects beyond our galaxy—sources that cannot be fully understood through light alone.
Now, scientists are taking the next step with IceCube-Gen2 (Gen2), a next-generation observatory designed to be more than five times as sensitive as the current detector. At the heart of this ambitious project is Professor Aya Ishihara of the Institute for Advanced Academic Research and International Center for Hadron Astrophysics, who is leading the development of high-precision photodetectors for Gen2. What can we learn by turning the Antarctic ice into a giant telescope? And what might the next generation of IceCube reveal about the high-energy universe? We spoke with Professor Ishihara about the journey so far, the challenges ahead, and what continues to drive her curiosity as a researcher.