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Imposing time-dependent strain on a magnetic disk induces vortex dynamics and offers a path toward energy-efficient spintronic devices.

Nanoscopic magnetic vortices made from electron spins could be used in spintronic computers (see Research News: 3D Magnetism Maps Reveal Exotic Topologies). To this end, researchers need an energy-efficient way to excite these vortices into a so-called gyrotropic mode—an orbital motion of the vortex core around the central point. The direction of this orbital motion would determine which of two binary states the vortex represents. Vadym Iurchuk at the Helmholtz-Zentrum Dresden-Rossendorf, Germany, and his colleagues have now demonstrated such a method by imposing a time-varying strain on a magnetic material [1].

The excitation of gyration dynamics by an oscillating strain was suggested by a separate team in 2015 [2]. The idea involves depositing a magnetic film, in which magnetic vortices form spontaneously, on a piezoelectric substrate. Applying an alternating voltage to the substrate transfers a time-varying mechanical strain to the film, dynamically perturbing its magnetic texture. This perturbation displaces a vortex core from its equilibrium position, thereby exciting the gyrotropic mode.

Living organisms constantly navigate dynamic and noisy environments, where they must efficiently sense, interpret, and respond to a wide range of signals. The ability to accurately process information is vital for both executing interspecies survival strategies and for maintaining stable cellular functions, which operate across multiple temporal and spatial scales [1] (Fig. 1). However, these systems often have access to only limited information. They interact with their surroundings through a subset of observable variables, such as chemical gradients or spatial positions, all while operating within constrained energy budgets. In this context, Giorgio Nicoletti of the Swiss Federal Institute of Technology in Lausanne (EPFL) and Daniel Maria Busiello of the Max Planck Institute for the Physics of Complex Systems in Germany applied information theory and stochastic thermodynamics to provide a unified framework addressing this topic [2]. Their work has unraveled potential fundamental principles behind transduction mechanisms that extract information from a noisy environment.

Bacteria, cells, swarms, and other organisms have been observed acquiring information about the environment at extraordinarily high precision. Bacteria can read surrounding chemical gradients to reach regions of high nutrients consistently [3], and cells form patterns during development repetitively and stably by receiving information on the distribution and concentration of external substances, called morphogens [4]. In doing so, they must interact with a noisy environment where the information available is scrambled and needs to be retrieved without corrupting the relevant signal [5]. All this comes at a cost.

The idea that precision is not free is an old one in the field of stochastic thermodynamics, and the cost usually comes in the form of energy dissipation [6]. This trade-off is even more relevant for biological systems that have limited access to energy sources. Living systems are pushed to find optimal strategies to achieve maximum precision while minimizing energy consumption. Consequently, a complete quantitative description of how these strategies are implemented requires the simultaneous application of information theory and stochastic—that is, noisy—thermodynamics.

An infrared detector is sensitive to a wide range of intensities and could potentially pick up biomarkers from exoplanet atmospheres.

Many areas of astrophysics, cosmology, and exoplanet research would benefit from a highly sensitive and stable detector for light at wavelengths in the 10–100 µm range. Now researchers report building a detector that operates at 25 µm and that is suitable for hours-long operation in a telescope pointed at faint sources [1]. The device exploits the extreme sensitivity to light of a superconducting material patterned into a miniature photo-absorptive structure. The researchers expect that the design will find use in space telescopes launched in the next few years.

Light at wavelengths in the range 10–100 µm may carry crucial spectroscopic clues about biogenic gases in exoplanet atmospheres and could also help astrophysicists pin down details of early planetary formation and galactic evolution. Yet building detectors for this range of wavelengths is challenging for several reasons, says astrophysicist Peter Day of the California Institute of Technology (Caltech). Because the light from these sources is so faint, the detector has to perform stably over many hours of observation. Each pixel of the detector has to be capable of registering single photons yet also be accurate for sources as much as 100,000 times brighter than the faintest detectable source. The detector must also have an efficient way to read out information rapidly from thousands of identical pixels.

A short-lived combination of an electron and an antielectron has been cooled with lasers to near absolute zero—a step toward tackling fundamental questions about matter and antimatter.

Successful reduction of the chemical manufacturing industry’s environmental impact relies on finding a greener way to make the chemical building blocks for common and massively consumed compounds.

In 2023, the NASA OSIRIS-REx mission returned a sample of dust and rocks collected on the near-Earth asteroid Bennu. In addition to the information about the universe gleaned from the sample itself, the data generated by OSIRIS-REx might also present an opportunity to probe new physics. As described in Communications Physics, an international research team led by Los Alamos National Laboratory used the asteroid’s tracking data to study the possible existence of a fifth fundamental force of the universe.

Fusion researchers are increasingly turning to the element tungsten when looking for an ideal material for components that will directly face the plasma inside fusion reactors known as tokamaks and stellarators. But under the intense heat of fusion plasma, tungsten atoms from the wall can sputter off and enter the plasma. Too much tungsten in the plasma would substantially cool it, which would make sustaining fusion reactions very challenging.

Researchers from Tohoku University and the Massachusetts Institute of Technology (MIT) have unveiled a new AI tool for high-quality optical spectra with the same accuracy as quantum simulations, but working a million times faster, potentially accelerating the development of photovoltaic and quantum materials.

Scientists are finding ways to use quantum effects to create groundbreaking thermal devices that can help cool electronic systems. The quantum thermal transistor is one of the most exciting innovations in this field. While the current works surrounding this device are still theoretical, recent advancements in the fabrication of qubits using quantum dots and superconducting circuits have created a growing sense of optimism.