Magnetic skyrmion crystal (SkX) configurations were first theoretically proposed and then experimentally observed in chiral magnets. SkX formations have also been found in centrosymmetric magnets stabilized by competing exchange or dipolar interactions. Because of their topological nature and potential applications in spintronics, magnetic skyrmions have been a central focus in condensed matter physics over the past decade.
In this Physical Review Letters article, a CINT User team explores the emergence of SkXs within non-Kramers doublet systems. In these systems, all constituents of the skyrmions are multipolar moments devoid of any dipolar character. The distinct symmetry properties of these underlying multipolar moments suggest that non-Kramers skyrmions may harbor novel physics that is not shared by their dipolar counterparts. CINT highlight slide here.
Full article here: Multipolar Skyrmion Crystals in Non-Kramers Doublet Systems
Digital light process (DLP) 3D printing is an increasingly widespread vat polymerization method for producing complex 3D structures using additive manufacturing.
In this Advanced Materials article, a CINT User team documents the preparation of aligned, main-chain LCEs via DLP 3D printing using a 100 mT magnetic field. CINT highlight slide here.
Full article here: Digital Light Process 3D Printing of Magnetically Aligned Liquid Crystalline Elastomer Free–forms
Excitons – quasi-particle bound states of electron–hole pairs – are investigated extensively as they serve as the foundation of almost all modern photonic technologies. The efforts of the past decades focused on uncorrelated excitons in conventional semiconductors where quasi-particles weakly interact with one another. Currently, correlated excitons are generating significant interest due to their intrinsic many-body interactions entangling charge, spin, orbital, and lattice degrees of freedoms.
In this Nanoscale Horizons article, a CINT User team shows that by reducing the lateral dimension of correlated antiferromagnet NiPS3 flakes to tens of nanometers and thickness to less than ten nanometers, we can switch-off the bulk spin–orbit entangled exciton in the near-infrared (1.47 eV) and activate visible-range (1.8–2.2 eV) transitions. CINT highlight slide here.
Full article here: Correlated Excitons in a Nanoscale 2D-Antiferromagnet
Atomic defects in crystals are a promising platform for constructing quantum networks, in which individual defects are connected over long distances using light. Such networks could lead to a new generation of quantum sensors, quantum computers, and quantum communication techniques.
In this accepted Physical Review X article, a CINT User team shows this high-fidelity readout is compatible with other advantages of this qubit, and is ready for application in quantum technologies. CINT highlight slide here.
Full article here: Single-Shot Readout and Weak Measurement of a Tin-Vacancy Qubit in Diamond
Exceptional points (EPs) — singularities in the parameter space of non-Hermitian systems where two nearby eigenmodes coalesce — feature unique properties with applications such as sensitivity enhancement and chiral emission. Existing realizations of EP lasers operate with static populations in the gain medium.
In this Nature article, a CINT User team including CINT Scientist Alex Cerjan analyzes full-wave Maxwell–Bloch equations to show that in a laser operating sufficiently close to an EP, the nonlinear gain will spontaneously induce a multi-spectral multi-modal instability above a pump threshold, which will initiate an oscillating population inversion and generate a frequency comb. CINT highlight slide here.
Full article here: Dynamic Gain and Frequency Comb Formation in Exceptional-Point Lasers.
Sodium ion batteries (SIBs) and sodium metal batteries (SMBs) are promising options in next- generation energy storage technology. However, before sodium metal can be rightfully considered as a viable anode it has to overcome the critical challenge of interfacial instability during electrodeposition/dissolution. For anode-free SMBs (AF-SMBs), where the cathode is the only ion reservoir, the challenge is to achieve stable electrodeposition/dissolution onto an "empty" current collector, rather than onto pre-existing sodium metal.
In this Angewandte Chemie article, a CINT User team including CINT Scientist John Watt employs a model system based on a lithiophilic composite of Na2Te intermetallics and Cu microparticles. The key rationale for using this composite support is that it "does not move", i.e. there are no volume changes during electrodeposition/dissolution of Na. Both Na2Te and Cu are thermodynamically stable at anode-relevant voltages. During cycling such supports do not react with Na, and yet remain highly sodiophilic due to the nature of the electronic structure of the alkaline-ion containing intermetallic. CINT highlight slide here.
Full article here: Interdependence of Support Wettability - Electrodeposition Rate- Sodium Metal Anode and SEI Microstructure
Safe, efficient, and reliable batteries are critical to the future of an electricity-based society. A critical component of commercially relevant batteries is the electrolyte, and new electrolyte materials are necessary for next-generation batteries. Synthetic polymers have been suggested as one possibility, as they have excellent mechanical and chemical stability and some can dissolve lithium salts.
In this Chemistry of Materials article, a CINT User team including CINT Scientists Amalie Frischknecht and Mark Stevens demonstrate that a multiblock lithium-ion-conducting polymer can be swollen with ethylene carbonate solvent to increase the conductivity relative to the dry polymer material by nearly 4 orders of magnitude. CINT highlight slide here.
Full article here: Partial Solvation of Lithium Ions Enhances Conductivity in a Nanophase-Separated Polymer Electrolyte
Extensive efforts have been dedicated to improving optoelectronic and light harvesting functions of dendrimers through the optimization of their topologies, structural rigidity, and electronic-vibrational (vibronic) couplings. For instance, initial investigations revealed the pivotal role of building block connectivity and topology in dendritic structures.
In this Journal of the American Chemical Society article, a CINT User team working with CINT Scientist Sergei Tretiak shows how charge migration in a dendrimer can be manipulated by placing it in an optical cavity and monitored by time-resolved X-ray diffraction. Their simulations demonstrate that the dendrimer charge migration modes and the character of photoexcited wave function can be significantly influenced by the strong light-matter interaction in the cavity. This presents a new avenue for modulating initial ultrafast charge dynamics and subsequently controlling coherent energy transfer in dendritic nanostructures. CINT highlight slide here.
Full article here: Cavity Manipulation of Attosecond Charge Migration in Conjugated Dendrimers
Quantum ghost imaging (QGI) is a method that measures absorption at extremely low light intensities. Nondegenerate QGI probes a sample at one wavelength while forming an image with correlated photons at a different wavelength. This spectral separation alleviates the need for imaging detectors with high sensitivity in the near-infrared (NIR) region, thereby reducing the required illumination intensity.
In this Optica article, a CINT User team uses NCam, a single-photon detector to demonstrate nondegenerate QGI with unprecedented sensitivity and contrast, obtaining images of living plants with less than 1% light transmission.shows that analog photonic encoders could address this challenge, enabling high-speed image compression using orders-of-magnitude lower power than digital electronics. CINT highlight slide here.
Full article here: Infrared Quantum Ghost Imaging of Living and Undisturbed Plants
In the recent years, photonic Chern materials have attracted substantial interest as they feature topological edge states that are robust against disorder, promising to realize defect-agnostic integrated photonic crystal slab devices. However, the out-of-plane radiative losses in those photonic Chern slabs has been previously neglected, yielding limited accuracy for predictions of these systems’ topological protection.
In this Nanophotonics article, a CINT User Team including CINT Scientist Alexander Cerjan develops a general framework for measuring the topological protection in photonic systems, such as in photonic crystal slabs, while accounting for in-plane and out-of-plane radiative losses. CINT highlight slide here.
Full article here: Classifying Topology in Photonic Crystal Slabs with Radiative Environments.
Current reports of thermal expansion coefficients (TEC) of two-dimensional (2D) materials show large discrepancies that span orders of magnitude. Determining the TEC of any 2D material remains difficult due to approaches involving indirect measurement of samples that are atomically thin and optically transparent.
In this ACS Nano article, a CINT User team presents a substrate-free experimental characterization technique to directly measure the localized thermal expansion coefficient of the polycrystalline 2D TMD material WSe2, using 4-dimensional scanning transmission electron microscopy (4D-STEM) paired with complex computational data analysis.
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Full article here: Direct Measurement of the Thermal Expansion Coefficient of Epitaxial Wse2 by Four-Dimensional Scanning Transmission Electron Microscopy
Thermal conductivity is a powerful transport probe of a superconducting state. The superconducting condensate does not carry heat current; only normal quasiparticles participate in electronic (charge) thermal transport. As a result, thermal conductivity is exquisitely sensitive to the structure of the superconducting energy gap
In this Physical Review Letters article, a CINT User Team demonstrates that the thermal-conductivity measurement in rotating magnetic field can probe the normal parts of the Fermi surface deep inside the superconducting state.
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Full article here: Normal Fermi Surface in the Nodal Superconductor CeCoIn5 Revealed via Thermal Conductivity
Modern lens designs are capable of resolving greater than 10 gigapixels, while advances in camera frame-rate and hyperspectral imaging have made data acquisition rates of Terapixel/second a real possibility. The main bottlenecks preventing such high data-rate systems are power consumption and data storage.
In this Nature Communications article, a CINT User team shows that analog photonic encoders could address this challenge, enabling high-speed image compression using orders-of-magnitude lower power than digital electronics. Our approach relies on a silicon-photonics front-end to compress raw image data, foregoing energy-intensive image conditioning and reducing data storage requirements. The compression scheme uses a passive disordered photonic structure to perform kernel-type random projections of the raw image data with minimal power consumption and low latency. A back-end neural network can then reconstruct the original images with structural similarity exceeding 90%. This scheme has the potential to process data streams exceeding Terapixel/second using less than 100 fJ/pixel, providing a path to ultra-high-resolution data and image acquisition systems.
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Full article here: Integrated Photonic Encoders for Ultrafast and Low Power Image Processing
Aluminum oxide (Al2O3) is known to stabilize the SEI of lithium and sodium metal batteries. However, it is not feasible to employ standard physical vapor deposition (PVD) and chemical vapor deposition routes (CVD) routes to coat it onto low melting-point K anodes.
In this Angewandte Chemie article, a CINT User Team including CINT Scientist John Watt addresses this challenge by room-temperature spin coating 10 μm films of Al2O3 nanopowder onto both sides of a commercial polypropylene separator.
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Full article here: Alumina — Stabilized SEI and CEI in Potassium Metal Batteries
Numerous physical (top-down) and chemical (bottom-up) approaches to NP synthesis have been applied for the synthesis of ZnO and other NPs. The former, however, tends to be energy intensive, while the latter often requires the use of toxic reducing agents, and/or non-aqueous organic solutions, impacting their biomedical potential. Both of these conventional approaches also require extreme conditions with regard to temperature, pressure, or pH, presenting barriers in the areas of energy consumption, cost, and environmental toxicity.
In this Nanoscale article, a CINT User Team that included CINT Scientists John Watt and George Bachand, as well as CINT Technical Specialist Winson Kuo suggests that small molecule metabolites present in fungal exudates play a key role in the mycosynthesis of well-defined NPs, while the composition and concentration of proteins is less important. Learn more about this research. CINT highlight slide here.
Full article here: Identifying Biochemical Constituents Involved in the Mycosynthesis of Zinc Oxide Nanoparticles
Ultralow-noise laser sources are crucial for a variety of applications, including microwave synthesizers, optical gyroscopes and the manipulation of quantum systems. Silicon photonics has emerged as a promising solution for high-coherence applications due to its ability to reduce the system size, weight, power consumption, and cost.
In this research published in Nature Photonics, a CINT User Team working with CINT Affiliate Scientist Weng Chow demonstrates quantum-dot lasers grown directly on Si that achieve self-injection-locking laser coherence under turnkey external-cavity locking. CINT highlight slide here.
Full article here: Turnkey Locking of Quantum-dot Lasers directly Grown on Si
Confining materials to two-dimensional forms changes the behaviour of the electrons and enables the creation of new devices. However, most materials are challenging to produce as uniform, thin crystals.
In this research published in Nature Materials, a CINT User Team working with CINT Scientist Michael Pettes demonstrates that the atomically smooth nature of van der Waals materials such as hexagonal boron nitride make them ideal nanoscale molds for confined crystal growth, shown here to obtain 2D bismuth. CINT highlight slide here.
Full article here: Exceptional Electronic Transport and Quantum Oscillations in Thin Bismuth Crystals Grown inside van der Waals Materials
Si/Ge heteroepitaxial growth yields pristine host material for quantum dot qubits, but residual interface disorder can lead to qubit-to-qubit variability that might pose an obstacle to reliable Si/Ge-based quantum computing.
In this research published in npj Quantum Information, a CINT User Team working with CINT Scientist Andrew Mounce and CINT Affiliate Scientist Ezra Bussmann reconstruct 3D interfacial atomic structure and employ an atomistic multi-valley effective mass theory to quantify qubit spectral variability. CINT highlight slide here.
Full article here: Modeling Si/SiGe Quantum Dot Variability Induced by Interface Disorder Reconstructed from Multiperspective Microscopy
Materials that can toggle between two states with distinct properties are important for information storage technology. Phase-change materials, for example, have been widely used for rewriteable optical data storage. They are valued not only for their versatile tunability but also for the low dimensionality that allows exotic properties to arise due to quantum confinement.
In this Nature Communications article, a CINT User team including CINT Scientist Jian-Xin Zhu demonstrates the non-volatile reversible switching of two closely related crystal structural phases in the vdW ferromagnet Fe5GeTe2 via an annealing and quenching procedure. CINT highlight slide here.
Full article here: Reversible Non-volatile Electronic Switching in a near-Room-Temperature van der Waals Ferromagnet
With results from real and reciprocal space, this study strives to correlate the effects of clustering on the translation of constraint dynamics from the atomistic level and segmental length scales to the overall motion of the polymers, using suflonated polystyrene in the ionomer regime
In this ACS Polymers article, results show that in melts, dynamics of the polymer depends on the counterion and cluster morphology. CINT highlight slide here.
Full article here: From Molecular Constraints to Macroscopic Dynamics in Associative Networks Formed by Ionizable Polymers
Development of shale gas and tight oil reserves could lead to a projected increase in the natural gas production of 100 % by the year 2050. Methane accounts for 70–90 mol.% of the shale gas feed composition depending on the location of the shale gas source. Despite the large availability of this carbon resource, current methane conversion methodologies are limited.
In this Chemical Engineering Journal article, non-oxidative coupling of methane provides as a means for carbon efficient conversion of methane to higher hydrocarbons. CINT highlight slide here.
Full article here: Catalytic Reactivity of Pt Sites for Non-oxidative Coupling of Methane (NOCM)
Traditional microelectronic architectures, with transistors to control electrical currents along wires, power everything from advanced computers to everyday devices. But with the integrated circuits offering diminishing returns in terms of speed and adaptability, Los Alamos National Laboratory scientists are developing nanometer-scale light-based systems that could deliver breakthroughs for ultrafast microelectronics, room-temperature infrared detection (for example, night vision) and a wide variety of technological applications.
As described in an article just published in Nature, the research team designed and fabricated asymmetric, nano-sized gold structures on an atomically thin layer of graphene. The gold structures are dubbed “nanoantennas” based on the way they capture and focus light waves, forming optical “hot spots” that excite the electrons within the graphene. Only the graphene electrons very near the hot spots are excited, with the rest of the graphene remaining much less excited. CINT highlight slide here.
Full article here: Light-driven Nanoscale Vectorial Currents
The fine-tuning of topologically protected states in quantum materials holds great promise for novel electronic devices. However, there are limited methods that allow for the controlled and efficient modulation of the crystal lattice while simultaneously monitoring the changes in the electronic structure within a single sample.
Here, we apply significant and controllable strain to high-quality HfTe5 samples and perform electrical transport measurements to reveal the topological phase transition from a weak topological insulator phase to a strong topological insulator phase. CINT highlight slide here.
Full article here: Controllable Strain-Driven Topological Phase Transition and Dominant Surface-State Transport in HFTE5
