Top 50: Physics

Organic semiconductors provide a platform for flexible lasers, but these are still produced on rigid, thick substrates. Here, Karl et al. develop a method to make freestanding membrane lasers that can be transferred onto any substrate and show that these could be used as anti-counterfeiting labels.

Some animals have multimodal locomotive capabilities to survive in different environments. Inspired by nature, Chen et al. build a centimeter-scaled robot that is capable of walking on water, underwater, on land, and transiting among all three, whose ‘feet’ break water by modifying surface tension.

Artificial intelligence is now superior to humans in many fully competitive games, such as Chess, Go, and Poker. Here the authors develop a machine-learning algorithm that can cooperate effectively with humans when cooperation is beneficial but nontrivial, something humans are remarkably good at.

Quantum mechanics is expected to provide a consistent description of reality, even when recursively describing systems contained in each other. Here, the authors develop a variant of Wigner’s friend Gedankenexperiment where each of the current interpretations of QM fails in giving a consistent description.

Despite the enormous potential of magnetically-guided soft robots for various applications, challenges related to inefficient locomotion in harsh environments hinder its development. Here, the authors demonstrate a multi-legged millirobot with excellent locomotion capability in harsh environments.

Thermal imaging of a sample simultaneously with standard microscopy often requires complex modifications to the microscope. Here, Zhao et al. design a simple non-Hermitian structure that can be coated onto a glass slide where exceptional-point enhanced thermal sensing enables this capability.

Who benefits from sharing data? The scientists of future do, as data sharing today enables new science tomorrow. Far from being mere rehashes of old datasets, evidence shows that studies based on analyses of previously published data can achieve just as much impact as original projects.

Manipulation of paramagnetic microparticles can be exploited for drug delivery. Here the authors manipulate a swarm of such particles and control its shape with a magnetic field so that it can elongate reversibly, split into smaller swarms and thus be guided through a maze with multiple parallel channels.

Neutron beams are useful studying fundamental physics problems, fusion process and material properties. Here the authors use intense laser irradiation of deuterated nanowire array targets to create high energy density plasmas capable of efficient generation of ultrafast neutron pulses.

The exact mechanism of momentum conversion from light to an object has varied descriptions in the literature and experimental verifications are difficult. Here the authors do an in-depth experimental and numerical study of the momentum dynamics of elastic waves in a dielectric mirror hit by a pulsed laser beam.

Multiplexed vortex light beams are promising for optical communications, but efficient mode sorting is so far limited to bulk optics. Here the authors develop a scalable vortex beam sorter that uses a plasmonic topological insulator structure to spatially separate the modes to resolve them on a standard CMOS detector.

The application of strain to semiconducting materials can be used to engineer electric fields through a varying energy gap. Here, the authors observe an inverse charge-funnel effect in atomically thin HfS₂, enabled by strain-induced electric fields.

Donor impurities in silicon are promising candidates as qubits but in order to create a large-scale quantum computer inter-qubit coupling must be introduced by precise positioning of the donors. Here the authors demonstrate the fabrication, manipulation and readout of a two qubit phosphorous donor device.

Silicon-based contaminants are ubiquitous in natural graphite, and they are thus expected to be present in exfoliated graphene. Here, the authors show that such impurities play a non-negligible role in graphene-based devices, and use high-purity parent graphite to boost the performance of graphene sensors and supercapacitor microelectrodes.

Assembly of higher-order artificial vesicles can unlock new applications. Here, the authors use optical tweezers to construct user-defined 2D and 3D architectures of chemically distinct vesicles and demonstrate inter-vesicle communication and light-enabled compartment merging.

Martensitic transition is commonly seen in steel and shape memory alloys but rarely in organic materials. Chung et al. discover martensitic transitions in organic electronics and utilize it in designing field-effect transistors, leading to shape memory effect that in return modifies charge transport properties.

The fabrication of van der Waals heterostructures of atomically thin materials often relies on the search, manual transferring, and alignment of suitable flakes. Here, the authors develop a robotic system capable of identifying exfoliated 2D crystals and assembling them in complex heterostructures.

Manipulation at the atomic scale comes with a trade-off between simplicity and thermal stability. Here, Achal et al. demonstrate improved automated hydrogen lithography and repassivation, enabling error-corrected atomic writing of large-scale structures/memories that are stable at room temperature.

The interplay between superconductivity and charge density wave (CDW) in 2H-NbSe₂ is still not fully understood. Here, Cho et al. use controlled disorder to probe the interplay between these two phases in 2H-NbSe₂ and find that superconductivity initially competes with CDW but eventually long-range CDW order assists superconductivity.

By using a near-IR optical excitation, upconverting nanoparticles may enable high-resolution imaging deep in tissue. Here, Tian et al. introduce alloyed upconverting nanoparticles with improved brightness due to newly described energy transfer pathways.

Hot carriers have excess energy that could be used to enhance solar cell efficiencies if their lifetimes are sufficiently long. Here, Fang et al. observe nanosecond hot carrier lifetime by photoluminescence in formamidinium tin triiodide perovskites which is 1000 times higher than lead based perovskites.

Conventional distributed Brillouin sensing allows real-time sampling at high spatial resolution, but is so far restricted to measuring quantities inside the fibre core. Here, Chow et al. demonstrate a distributed forward Brillouin sensor that is sensitive to quantities outside the fibre bulk.

Silicon-vacancy centres in diamond are promising candidates as emitters in photonic quantum networks, but their coherence is degraded by large electron-phonon interactions. Sohn et al. demonstrate the use of strain to tune a silicon vacancy’s electronic structure and suppress phonon-mediated decoherence.

Exploring astrophysical turbulent effects in laboratory plasma is challenging due to high threshold values of relevant parameters, such as the magnetic Reynolds number. Here the authors demonstrate the turbulent dynamo effect at large magnetic Reynolds numbers in laser-generated magnetized plasma.

There is a continuous effort to improve the accuracy of atomic clocks. Here the authors measure the static differential scalar polarizability of Lutetium ion resonant transitions and its lower light shift from blackbody radiation makes it a promising candidate for ion-based atomic clocks.

The large data generated in heavy-ion collision experiments require careful analysis to understand the physics. Here the authors use the deep-learning method to sort equation of states in QCD transition and analyze the simulated data sets mimicking the heavy-ion collision experiments.

On-chip spectrometers typically have limited spectral channels and low signal to noise ratios. Here the authors introduce a digital architecture that uses switches to change the interferometer path lengths, enabling exponentially more spectral channels per circuit element and lower noise by leveraging a machine learning reconstruction algorithm.

Memristive technology is a promising avenue towards realizing efficient non-von Neumann neuromorphic hardware. Boybat et al. proposes a multi-memristive synaptic architecture with a counter-based global arbitration scheme to address challenges associated with the non-ideal memristive device behavior.

Memristors have become an emerging technology capable in emulating human brain information processing, but understanding and controlling the switching mechanism remains elusive. Here, Milano et al. combine memristive and neuromorphic functionalities in a single crystalline nanowire model system.

X-ray detectors based on low-cost organic semiconductors have inherently low detector sensitivity due to poor X-ray to charge conversion and charge collection. Here, the authors demonstrate a flexible, high-sensitivity X-ray detector based on an organic bulk heterojunction-nanoparticle composite.

Plasma releases magnetic energy by magnetic reconnection but the clear evidence of this phenomenon in relativistic regime is still lacking. Here the authors present a scheme for laboratory observation of the relativistic magnetic reconnection driven by laser-produced energetic electrons in the plasma.

Acoustic bianisotropy does not exist in natural materials but can be designed with acoustic metamaterials. Here, Li et al. utilized acoustic bianisotropy and develop a practical metamaterial with improved transmission efficiency which outperforms the Generalized Snell’s Law.

Light in biological media is known as freely diffusing because interference is negligible. Here, the authors demonstrate Anderson localization of light from quasi-two-dimensional nanostructures in silk fibres.

Many complex oxides combine multiple functionalities that can be manipulated by external fields, providing opportunities for creating devices. Here, He et al. predict that Ag₂BiO₃ can be tuned between ferroelectric and different topological semimetallic states using electric fields at room temperature.

Mid-IR optics can require exotic materials or complicated processing, which can result in high cost and inferior quality. Here the authors report the demonstration of high-efficiency mid-IR transmissive lenses based on dielectric Huygens metasurface, showing diffraction limited focusing and imaging performance.

Spectroscopic evidence of equal-spin triplet Cooper pairs is still missing so far. Here, Diesch et al. propose a unique signature for the presence of equal-spin triplet pairs and experimentally reveal the spin configuration of triplet pairs at the Al/EuS interface.

The electron affinity of liquid water is a fundamental property which has not yet been accurately measured. Here, the authors predict this property by coupling path-integral molecular dynamics with ab initio potentials and electronic structure calculations, revisiting several estimates used in the literature.

Here, the authors demonstrate an array of superconducting qubits embedded into a microwave transmission line. They show that the transmission through the metamaterial periodically depends on externally applied magnetic field and suppression of the transmission is achieved through field-induced transitions.

The existence of multiple topological phases in a single material, although theoretically possible, has not been verified. Here, the authors observe weak topological insulator surface states and a one-dimensional Dirac-node crossing surface state in a single metallic material Hf₂Te₂P.

Superconductivity is evidenced in crystals and amorphous solids, but remains to be discovered in quasicrystals. Here, Kamiya et al. report the emergence of bulk superconductivity in Al-Zn-Mg quasicrystal at a very low transition temperature about 0.05 K.

Photoionization of atoms and molecules is a complex process and requires sensitive probes to explore the ultrafast dynamics. Here the authors combine transient absorption and photo-ion spectroscopy methods to explore and control the attosecond pulse initiated excitation, ionization and Auger decay in Kr atoms.

Optical filters are an integral part of many optical devices and circuits. Here, Magden et al. use a design based on mode evolution to demonstrate CMOS-compatible dichroic filters with more than an octave bandwidth, sharp roll-off and transmissive short- and long-wavelength outputs

It is a challenge to scale up laser-ion acceleration to higher ion energies. Here the authors demonstrate a hybrid acceleration scheme based on the relativistic induced transparency mechanism using linearly polarised laser interaction with foil targets and its future implication in using high power lasers.

The understanding of the reemergence of pressure induced superconductivity in alkali-metal intercalated FeSe is hampered by sample complexities. Here, Sun et al. report the electronic properties of (Li_1–xFe _x )OHFe_1–ySe single crystal not only in the reemerged superconducting state but also in the normal state.

Neuromorphic hardware is based on principles of neuroscience, and has the potential to provide higher-level brain functions. Here, the authors develop a neuromorphic network device, constructed from single-walled carbon nanotubes and polyoxometalate, that mimics nerve impulse generation.

Authenticating a nuclear warhead without revealing its design is a challenge. Here the authors discuss a nuclear disarmament verification method based on neutron resonance analysis which is sensitive to the isotopic composition of the materials used in warheads.

Entanglement between photons and stationary quantum nodes is a fundamental resource for quantum communication, but typical transition wavelengths are far from the telecom band. Here, the authors deal with the problem using polarisation-independent, entanglement-preserving frequency conversion.

Charge-to-spin conversion is a key theme of spintronics and its realization in topological materials is highly desired. Here, Liu et al. report spatial imaging of current-induced spin accumulation at the edges of Bi₂Se₃ and BiSbTeSe₂ topological insulators.

Cold atom clocks are among the most precise measuring devices and play key roles in everyday life and scientific explorations. Here the authors demonstrate the first in-orbit atomic clock using cold Rb atoms operating in microgravity and opening possibilities of space surveys and tests of fundamental physics.

Proper design of the gratings can enhance the efficiency of distributed-feedback and quantum cascade lasers. Here, Jin et al. use a hybrid grating system that superposes second- and fourth-order Bragg gratings and achieve high radiative efficiency and a single-lobe radiation pattern.