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Unlike conventional lasers that require a uniform resonant cavity to operate, random lasers use a highly disordered gain medium in which scattering is dominant. Hokr et al. report Raman lasing from a bulk three-dimensional disordered medium whose intensity exceeds that of other random lasers by many orders of magnitude.

The authors develop a new metric to measure the error-corrected convergence rate of protein evolution, together with a heuristic algorithm to detect signals of adaptive protein convergence.

CdSe–CdS nanocrystals with a 100% quantum yield and completely quenched Auger processes at low temperatures are demonstrated.

The authors use systematic monitoring across the former USSR to investigate phenological changes across taxa. The long-term mean temperature of a site emerged as a strong predictor of phenological change, with further imprints of trophic level, event timing, site, year and biotic interactions.

Vertical-cavity surface-emitting lasers consist of an active medium in between two distributed Bragg reflectors. Czerniuk et al.show that the resonant mechanical modes of these periodic structures efficiently modulate the laser emission intensity with frequencies of up to 40 GHz.

Halide perovskites have a variety of attractive feature such as high quantum yield, and tunable optical properties, combined with easy fabrication. Here, Kirstein et al demonstrate spin-mode locking in CsPb(Cl0.56Br0.44)3 lead halide perovskite nanocrystals embedded in a fluorophosphate glass matrix, and a hole spin lifetime extending into the microsecond range.

Brillouin scattering microscopy is prone to artefacts and inconsistencies. This Consensus statement provides recommendations for measuring and reporting relevant parameters with the aim of standardizing protocols and improving the comparability of studies.

Despite remarkable optical properties in lead halide perovskites, spin control in these materials is largely unexplored. Herein Belykh et al. study the coherent spin dynamics of electrons and holes in cesium lead bromide perovskites, and evidence interaction of electron and lattice nuclear spins.

The Landé factors govern all the spin-related basic phenomena and are the key parameters which guide spintronics applications. Here, Kirstein et al. demonstrate a universal dependence of the Landé factors on the bandgap energy of several perovskite materials.

Photoconductive sampling of optical fields is a powerful measurement technique, but existing models fail to connect single-electron dynamics to measured signals. Here, the authors report a model that identifies the roles of electron-neutral scattering and mean-field charge interaction in photoconductive sampling.

Understanding the electron and nuclear spin interactions is essential to the application of quantum information devices. Here the authors report a step-like electron Larmor frequency versus external magnetic field due to the discretization of the total magnetic field by the nuclear spin bath in ZnSe:F.

Nuclear spins in solid-state systems present a promising platform for quantum information applications. Here the authors report evidence of the long-predicted entangled dark nuclear spin state via optical polarization of localized hole spins coupled to the nuclear bath in a lead halide perovskite semiconductor.

The surface of CdSe nanoplatelets can exhibit a paramagnetic behaviour that influences the polarization properties of the optical emission.

The Kerr and Faraday effects enable routing of light in an applied magnetic field. Now a new class of magneto-optical phenomena is proposed and demonstrated in which light emission is controlled perpendicular to the external magnetic field.

We integrate approximately one million aerial site measurements into regional emissions inventories for six regions in the USA, finding methane emission intensities that vary by more than a factor of ten.

Magneto-optical effects, where magnetic fields affect light propagating through a material, are of interest for photonic devices such as switches. The magneto-optical effect discovered here in metal-dielectric nanostructures shows a strong light modulation that is suitable for nanophotonic applications.

Nonmagnetic colloidal nanocrystals demonstrate magnetic properties due to spins of dangling bonds at their surface resulting in formation of dangling-bond magnetic polarons.

Attosecond transient reflectivity spectroscopy, in combination with extensive time-dependent density functional theory calculations, is used to study field-driven carrier injection in germanium in the time window of few femtoseconds around pulse overlap, paving a route towards achieving full optical control over charge carriers in semiconductors.

Exchange interactions are typically short-ranged as they depend on wavefunction overlap, but a long-ranged exchange is now seen in a hybrid ferromagnet–semiconductor system, which may be mediated by elliptically polarized phonons.

Conventional linear optical methods cannot probe within an inhomogeneously broadened ensemble of particles. Yang et al.demonstrate a spectroscopic technique based on fluctuation correlations that can reveal the underlying homogeneous linewidths of quantum dots in a low-power ensemble measurement.

A solid-state device is demonstrated that can detect the absolute offset between the carrier wave and envelope of an ultrashort pulse, the carrier–envelope phase. It holds promise for routine measurement and monitoring of the carrier–envelope phase in attosecond experimental set-ups.

The authors demonstrate a technique for coherently transferring quantum information from the orbital to the spin degrees of freedom of electrons in a semiconductor, and back again.

Integration of ferromagnetic and semiconducting elements is important for future devices capable of both processing and storing information. Korenevet al. describe a novel spin-separation effect in a ferromagnet/semiconductor quantum well hybrid and show the optical readout of hysteresis loops.

The spin state of electrons trapped in a quantum dot only lasts a few microseconds. Before this information is lost, it is useful to controllably rotate the spin as many times as possible. Laser pulses can now rotate electron spins in an ensemble of quantum dots in just a few picoseconds.

Manipulating magnetic orders by electric fields promises energy efficient spintronic applications. Here the authors demonstrate electrical control of s-p exchange interaction in a ferromagnet-semiconductor quantum well structure due to the phononic ac Stark effect.

A new magneto-optical material consisting of a nanostructured gold film on top of a ferromagnetic dielectric demonstrated significantly enhanced Faraday and Kerr effects.

When exposing a tungsten crystal to intense light, the travel times of emitted electrons differ by 110 attoseconds, depending on whether they were originally tightly bound to one atom in the crystal or delocalized over many atoms. This ability to directly probe fundamental aspects of solid-state electron dynamics could aid the further development of modern technologies such as electronics, information processing and photovoltaics.

Exposing a fused silica sample to a strong, waveform-controlled, few-cycle optical field increases the dielectric’s optical conductivity by more than 18 orders of magnitude in less than 1 femtosecond, allowing electric currents to be driven, directed and switched by the instantaneous light field.

Researchers use femtosecond laser pulses to create acoustic pulses that strain quantum dots and modulate their transition energies. When the quantum dots are housed in a microcavity, tuning the quantum dots to the optical resonance of the cavity causes the emission output to be enhanced by more than two orders of magnitude.

The ultrafast reversibility of changes to the electronic structure and electric polarizability of a dielectric with the electric field of a laser pulse, demonstrated here, offers the potential for petahertz-bandwidth optical signal manipulation.

Peptoids are synthetic polymers designed to mimic the structure and functionality of proteins. When a one-to-one blend of two oppositely charged peptoids is mixed in solution, giant, 2.7-nm-thick free-floating sheets are formed. The sheets can specifically bind a corresponding protein, and offer potential for producing functional two-dimensional nanostructures in the future.