Ammonia is a promising hydrogen carrier and fertilizer, with growing potential as a low-carbon fuel. However, conventional production is highly energy-intensive and contributes significantly to greenhouse gas emissions. In a new study, researchers developed a dual chemical looping strategy for ammonia synthesis that avoids several energy-intensive steps used in traditional processes. An integrated 4E analysis showed improved efficiency and robustness while reducing production costs.

A nanostructure made of silver and an atomically thin semiconductor layer can be turned into an ultrafast switching mirror device that may function as an optical transistor – with a switching speed around 10,000 times faster than an electronic transistor. An international team of researchers led by the University of Oldenburg, Germany, describes this effect in a paper published in the current issue of Nature Nanotechnology. Ultrafast light switches offer interesting prospects for optical data processing, chip manufacturing, optical sensors or quantum computers.

Researchers at the University of Oulu, Finland, have developed a pine‑bark–based water‑treatment medium that efficiently removes antibiotics as well as residues of blood‑pressure and antidepressant medicines from wastewater treatment plant effluent. A new doctoral thesis reports promising results with a simple and low‑cost method in which pine bark was modified with iron.

To overcome the lack of wavelength-selective extraction in existing on-chip metasurfaces, Chinese scientists developed a novel approach by leveraging a nonlocal on-chip design based on symmetry-broken quasi-bound states in the continuum (q-BICs) physics, enabling precise wavelength-selective extraction and color routing of guided waves. Beyond free-space spatial-multiplexing schemes, these on-chip cascaded-multiplexing architectures achieve a significant improvement in the energy utilization efficiency, offering a new pathway for high-efficiency spectral control and routing on chip-integrated metadevices.

For many years, cesium atomic clocks have been reliably keeping time around the world. But the future belongs to even more accurate clocks: optical atomic clocks. In a few years' time, they could change the definition of the base unit second in the International System of Units (SI). It is still completely open which of the various optical clocks will serve as the basis for this. The large number of optical clocks that the Physikalisch-Technische Bundesanstalt (PTB), as a leading institute in this field, has realized could be joined by another type: an optical multi-ion clock with ytterbium-173 ions. It could combine the high accuracy of individual ions with the improved stability of several ions. This is the result of a cooperation between PTB and the Thai metrology institute NIMT. The team led by Tanja Mehlstäubler reports on this in the current issue of the journal Physical Review Letters. The results are also interesting for quantum computing and, with a new look inside the atom, for fundamental research.

A new study by researchers in Japan offers new insights into how protocells may have inherited and enriched genetic material before modern biology emerged. By exposing mixed phospholipid vesicles to repeated freezing and thawing, the team found that vesicles with more unsaturated lipids grew more efficiently and became selectively enriched. This membrane-level selection also increased the fraction of selectively neutral genetic material trapped inside.

Researchers have demonstrated that intense laser fields, particularly at low frequencies, can significantly enhance nuclear fusion efficiency by modifying the effective collision energies of interacting nuclei. These findings suggest a possible pathway to improving fusion reaction rates without relying exclusively on extremely high plasma temperatures.

Scientists developed a two-photon-enhanced metasurface that cuts photon requirements for nanoscale displacement measurement in semiconductor lithography by 97%. Using entangled photons, the method achieves nanometer-level precision, accelerating alignment for next generation chip manufacturing. The system operates at 20–5000 nm/s, enabling faster, energy-efficient production without costly hardware upgrades.