Quantum cascade laser (QCL) frequency combs face bandwidth limitations (~100 cm⁻¹) that challenge carrier-envelope offset frequency locking. This work demonstrates ultra-broadband QCLs using a diagonal multi-state-to-continuum active region design, achieving ~600 cm⁻¹ electroluminescence at 298 K. Devices deliver 2.72 W peak power with 1.2 μm lasing bandwidth and 1.93 μm at 80 K, advancing single-stack mid-infrared semiconductor lasers for spectroscopy and communications.

Researchers have resolved a long-standing debate about how water behaves when confined to spaces just a few molecules wide, showing that the chemistry of nanoconfined water is governed less by confinement itself than by pressure and the nature of the surrounding material. This finding could help scientists design more efficient batteries, fuel cells and nanofluidic technologies by providing a new way of controlling water reactivity at the molecular scale.

A physics team led by the University of Iowa has described a “super expanded” magnetic cloud created by a coronal mass ejection on the sun. The team tracked the cloud as it approached Earth. The new information could lead to better predictions of future, super expanded magnetic clouds that could lead to satellite and telecommunications disruptions on Earth.