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Anti-Stokes luminescence - the emission of photons with higher energy than those absorbed – in nanomaterials is widely used for optoelectronic applications. Here the authors observe it in degenerately doped bulk InP and GaAs, indicating it as a more general property of direct bandgap semiconductors.

Coherent anti-Stokes Raman Scattering (CARS) accesses the vibrational properties of a material via nonlinear four-wave mixing (FWM); CARS in graphene has not been observed to date despite its high nonlinear third-order susceptibility. Here, the authors devised a FWM scheme to perform stimulated Raman spectroscopy in single and multi-layer graphene through CARS.

Fluorescence microscopy during CryoFIB milling produces an interferogram that can be used to direct lamella production to labeled structures with accuracy beyond the axial diffraction limit. The approach relies only on real-time feedback from the structure, requiring no image registration.

Solitonic modes that are redshifted due to a Raman-related effect are reported in optical microcavities, and termed Stokes solitons.

Li et al. report a spatially decoupled heavy atom antenna strategy by integrating alkyl bromides into a hybridized local and charge-transfer scaffold, originated from benzothiadiazole acceptors, to create an organic scintillator with a short radiative lifetime of 3.42 ns and spatial resolution around 50 lp mm^-1.

Microwaves are of interest for applications such as communications, radar and metrology. Here, Li et al. demonstrate an on-chip microresonator device for the generation of microwaves by optical means, instead of the usual electronic devices.

The authors present a scalable optical receiver platform that integrates a functional metasurface and ultrafast membrane InGaAs photodetector array on a compact chip. Detection of high-speed signals at up to 320 Gbit/s is experimentally demonstrated.

Given rising diabetes prevalence globally, access to diabetes treatments is gaining urgency. Here, the authors show patterns of glucose-lowering medication use for diabetes across 62 low- and middle-income countries.

An analogue to a type II burst from the early M dwarf StKM 1-1262 exhibits identical frequency, time and polarization properties to fundamental plasma emission from a solar type II burst.

Quantum-network protocols based on photon-atom interfaces have stimulated a great demand for single-photon sources with narrow bandwidth. Here the authors report the generation of entangled photon pairs with controllable bandwidth and coherence time from a Doppler-broadened hot atomic vapour cell.

Here, Kittlauset al. demonstrate stimulated inter-modal Brillouin scattering on-chip. Through this process, a Brillouin interaction couples light fields that propagate in distinct spatial modes of a Brillouin-active silicon waveguide, which may allow a variety of new processes in silicon photonics.

Exploiting photon–phonon coupling in nanoscale silicon waveguides could enable a host of powerful features in photonic devices. Using a hybrid photonic–phononic waveguide structure, Shin et al. show stimulated Brillouin scattering nonlinearities and gain, which offers new on-chip signal-processing abilities.

Optomechanical coupling to macroscopic phonon modes of a bulk acoustic-wave resonator is demonstrated, providing access to high acoustics quality factors for phononic modes at high frequencies that are robust to decoherence.

Here the authors developed on-chip microresonators with a remarkable Q-factor of 38 million and demonstrated on-chip Brillouin lasing in the mid-infrared. These results highlight opportunities to create more compact and efficient platforms for molecular science.

Antibacterial compounds are discovered by combining phenotypic screening with deep learning.

Kozai, Fernandez-Martinez et al. use high-speed atomic force microscopy to study the permeability barrier of yeast nuclear pore complexes. They show that karyopherins remodel a central plug that shapes barrier dynamics and disorder within the pore.

An investigation of the use of nonlinear upconversion effects like second-harmonic generation and four-wave mixing within biological tissue indicates that it should be possible to perform photodynamic therapy with near-infrared laser light at greater depths than previously.

Sources of chiral mid-infrared light are difficult to obtain. Here, the authors demonstrate that twisted bilayers of anisotropic α-MoO₃ van der Waals crystals can emit mid-infrared thermal chiral radiation without any lithographic processes.

In this work the authors demonstrate on-chip integration of Brillouin lasing operating at visible wavelengths, with engineered design for stable output. This technical and scientific advance will help develop integrated light sources for quantum computing or atomic and molecular spectroscopy.

Monolayer transition metal dichalcogenides host excitons, bound electron-hole pairs that play a pivotal role in optoelectronic applications relying on strong light-matter interaction. Here, the authors unveil the spectroscopic signature of boson scattering of two-dimensional excitons in monolayer WSe₂.

The repeating fast radio burst (FRB) source FRB 20121102A emits ultra-FRBs that last for only microseconds. These bursts are thousands of times shorter than typical for such astronomical radio flashes and indicate that there is a population of FRBs that has been missed previously.

Germano-silicate used as a building material for integrated photonics circuits substantially reduces optical losses, approaching levels comparable to those in optical fibres.

Inelastic X-ray scattering studies of YBa₂Cu₃O_6.6 reveal strong electron-phonon coupling and an inhomogeneous state made up of charge-density-wave nanodomains, which may explain some anomalous properties of the pseudogap state.

precisely controllable integrated optical gyroscope based on stimulated Brillouin scattering is used to study non-Hermitian physics, revealing a four-fold enhancement of the Sagnac scale factor near exceptional points.

Brillouin lasing with 0.7 Hz fundamental linewidth is observed by optically exciting a monolithic bus–ring Si₃N₄ waveguide resonator. The Brillouin laser is applied to an optical gyroscope and a low phase-noise photonic microwave oscillator.

This study shows that CrSBr hosts Frenkel-like and Wannier-Mott-like excitons whose distinct spatial character explains their contrasting sensitivity to magnetic order and lattice vibrations, challenging the standard dichotomy in describing excitons.

Using silicon nitride waveguides processed by plasma-enhanced chemical vapour deposition, full integration of ultrahigh-Q resonators with other photonic devices is now possible, representing a critical advance for future photonic circuits and systems.

Two-dimensional polyaramid polymers are synthesized to form nanofilms that exhibit the lowest gas permeability of any polymer by orders of magnitude, despite lacking crystallinity, enabling molecular-scale nanomechanical resonators and barrier materials.

Indium phosphide is the material of choice for bright and color-pure quantum dots for next-generation displays. This study identifies the photophysical processes that have until now prevented the development of lasers based on these particles.

Periodic pulsations of polarized emission and a strong magnetic field were found in a white-dwarf double system. These findings confirm a pulsar-like emission mechanism for the system that has so far been associated only with neutron stars.

The presence of magnetic fields in protostellar jets has been predicted theoretically, but its experimental confirmation has been elusive so far. Here, the authors report the detection of SiO line polarisation in the HH 211 protostellar jet, indicative of the onset of magnetic fields.

This study introduces P3T-Net, a pseudo-3D deep learning model that enables accurate and efficient cross-domain transfer of large 3D material images, improving image quality and ensuring image consistency across diverse imaging conditions.

The concept of dense random packing of hard spheres is well known to result in a packing fraction of 0.64, although this is difficult to observe in real systems. Here Ni et al.simulate the packing of self-propelled hard spheres, which allow them to achieve packing fractions close to the ideal value.

Non-reciprocal single-sideband modulation and mode conversion are realized in a low-loss integrated silicon waveguide, enabling >125 GHz operation bandwidths and up to 38 dB of non-reciprocal contrast between forward- and backward-propagating waves.

The West Antarctic Ice Sheet responded to different natural forcing mechanisms than the East Antarctic Ice Sheet through the mid-Pliocene due to a greater sensitivity to oceanic feedbacks, according to iceberg-rafted debris records and ice-sheet modelling experiments.

Fick’s laws describe the essential physics of diffusion, but it is challenging to extend them to systems out of equilibrium. The authors derive the diffusivity of particles near active carpets - a surface covered with hydrodynamic actuators, which provides a framework for transport in living matter.

This study explores how oral semaglutide (Rybelsus) crosses the gastrointestinal barrier. Findings suggest that semaglutide can embed in epithelial membranes with a permeation enhancer, offering molecular-level insight into oral peptide absorption.

An analysis of Zeeman measurements reveals that the reduction of magnetic flux relative to mass, which is necessary for star formation, seems to have occurred earlier than previously thought.

Lead halide perovskite nanocrystals show size-tunable optical properties. Here the authors reveal a non-monotonic size dependence of exciton radiative lifetime, suggesting optimal sizes for applications requiring fast photoemission.

Pulmonary type 2 inflammation is associated with type 2 innate lymphoid cells. Here the authors use the Collaborative Cross mouse panel to show that ILC2 abundance during type 2 lung inflammation is different across the panel and identify free-fatty acid receptor 3 (Ffar3) as a gene responsible and show cytokine and ILC2 functional changes.

The authors present 19 detections of coherent low-frequency radio emission from M dwarfs using the Low Frequency Array. The sample includes both chromospherically active and quiescent stars, but radio luminosities are independent of coronal and chromospheric activity indicators.

Quantum-dot-based single photon sources represent a promising resource for future quantum networks. Here, the authors realize all-photonic quantum teleportation using photons from two remote near-infrared-emitting quantum dots, using polarization-preserving quantum frequency converters to enable two-photon interference at telecom wavelength.

Two-dimensional fluid interfaces are ubiquitous, but studying their surface dynamic properties is difficult because of coupling between the film and bulk fluid. Choiet al.combine active microrheology with fluorescence microscopy to image fluid interfaces under applied stress.

During planetary formation segregation of an iron core from rocky silicates takes place. Here, the authors use analogue fluid experiments show that iron diapirs entrain volatiles and silicates to the Earth’s core and initiate buoyant thermochemical plumes to reoxidize and hydrate the upper mantle and atmosphere.

Difficulties in experimentally achieving simultaneous structural sensitivity and time resolution have hindered the real-time mapping of the vibrational energy relaxation pathways in biomacromolecules. Now, using ultrashort light pulses to locally deposit excess energy in a protein-bound haem, the temporal evolution of the subsequent energy flow has been monitored, unravelling vibrational couplings that lead to mode-specific temperature changes.