BINA

Weak values and Kirkwood--Dirac (KD) quasiprobability distributions have been independently associated with both foundational issues in quantum theory and advantages in quantum metrology. We propose simple quantum circuits to measure weak values, KD distributions, and density matrix spectra without the need for post-selection. This is achieved by measuring unitary-invariant, relational properties of quantum states, as functions of Bargmann invariants. Our circuits also enable direct experimental implementation of various applications of KD distributions, such as out-of-time-ordered correlators (OTOCs) and the quantum Fisher information in post-selected parameter estimation, among others. This results in a unified view of nonclassicality in all those tasks. In particular, we discuss how negativity and imaginarity of Bargmann invariants relate to set coherence.

Major advances in the precision of magnetic measurements bring us closer to quantum detection of individual spins at the single-atom level. On the quest for reducing both classical and quantum measurement noise, it is intriguing to look forward and search for precision limits arising from the fundamental quantum nature of the measurement process itself. Here, we present the limits of magnetic quantum measurements arising from quantum information considerations, and apply these limits to a concrete example of magnetic force microscopy (MFM). We show how such microscopes have a fundamental limit on their precision arising from the theory of imperfect quantum cloning, manifested by the entanglement between the measured system and the measurement probe. We show that counterintuitively, increasing the probe complexity decreases both the measurement noise and back action, and a judicious design …

Entanglement is a uniquely quantum resource giving rise to many quantum technologies. It is therefore important to detect and characterize entangled states, but this is known to be a challenging task, especially for multipartite mixed states. The correlation minor norm (CMN) was recently suggested as a bipartite entanglement detector employing bounds on the quantum correlation matrix. In this paper we explore generalizations of the CMN to multipartite systems based on matricizations of the correlation tensor. It is shown that the CMN is able to detect and differentiate classes of multipartite entangled states. We further analyze the correlations within the reduced density matrices and show their significance for entanglement detection. Finally, we employ matricizations of the correlation tensor for introducing a measure of global quantum discord.

Analysis of an individual's immunoglobulin or T cell receptor gene repertoire can provide important insights into immune function. High-quality analysis of adaptive immune receptor repertoire sequencing data depends upon accurate and relatively complete germline sets, but current sets are known to be incomplete. Established processes for the review and systematic naming of receptor germline genes and alleles require specific evidence and data types, but the discovery landscape is rapidly changing. To exploit the potential of emerging data, and to provide the field with improved state-of-the-art germline sets, an intermediate approach is needed that will allow the rapid publication of consolidated sets derived from these emerging sources. These sets must use a consistent naming scheme and allow refinement and consolidation into genes as new information emerges. Name changes should be minimised, but …

Engines are systems and devices that convert one form of energy into another, typically into a more useful form that can perform work. In the classical setup, physical, chemical, and biological engines largely involve the conversion of heat into work. This energy conversion is at the core of thermodynamic laws and principles and is codified in textbook material. In the quantum regime, however, the principles of energy conversion become ambiguous, since quantum phenomena come into play. As with classical thermodynamics, fundamental principles can be explored through engines and refrigerators, but, in the quantum case, these devices are miniaturized and their operations involve uniquely quantum effects. Our work provides a broad overview of this active field of quantum engines and refrigerators, reviewing the latest theoretical proposals and experimental realizations. We cover myriad aspects of these devices, starting with the basic concepts of quantum analogs to the classical thermodynamic cycle and continuing with different quantum features of energy conversion that span many branches of quantum mechanics. These features include quantum fluctuations that become dominant in the microscale, non-thermal resources that fuel the engines, and the possibility of scaling up the working medium's size, to account for collective phenomena in many-body heat engines. Furthermore, we review studies of quantum engines operating in the strong system-bath coupling regime and those that include non-Markovian phenomena. Recent advances in thermoelectric devices and quantum information perspectives, including quantum measurement …

Novel nanomaterials are of interest in biology, medicine, and imaging applications. Multimodal fluorescent-magnetic nanoparticles demand special attention because they have the potential to be employed as diagnostic and medication-delivery tools, which, in turn, might make it easier to diagnose and treat cancer, as well as a wide variety of other disorders. The most recent advancements in the development of magneto-fluorescent nanocomposites and their applications in the biomedical field are the primary focus of this review. We describe the most current developments in synthetic methodologies and methods for the fabrication of magneto-fluorescent nanocomposites. The primary applications of multimodal magneto-fluorescent nanoparticles in biomedicine, including biological imaging, cancer treatment, and drug administration, are covered in this article, and an overview of the future possibilities for these technologies is provided.

Metal transcription factors regulate metal concentrations in eukaryotic and prokaryotic cells. Copper is a metal ion that is being tightly regulated, owing to its dual nature. Whereas copper is an essential nutrient for bacteria, it is also toxic at high concentrations. CopY is a metal-sensitive transcription factor belonging to the copper-responsive repressor family found in Gram-positive bacteria. CopY represses transcription in the presence of Zn(II) ions and initiates transcription in the presence of Cu(I) ions. The complete crystal structure of CopY has not been reported yet, therefore most of the structural information on this protein is based on its similarity to the well-studied MecI protein. In this study, electron paramagnetic resonance (EPR) spectroscopy was used to characterize structural and local dynamical changes in Streptococcus pneumoniae CopY as a function of Zn(II), Cu(I), and DNA binding. We detected different …

Efficient and stable electrocatalysts are critically needed for the development of practical overall seawater splitting. The nanocomposite of RuCoBO has been rationally engineered to be an electrocatalyst that fits these criteria. The study has shown that a calcinated RuCoBO-based nanocomposite (Ru2Co1BO-350) exhibits an extremely high catalytic activity for H2 and O2 production in alkaline seawater (overpotentials of 14 mV for H2 evolution and 219 mV for O2 evolution) as well as a record low cell voltage (1.466 V@10 mA cm–2) and long-term stability (230 h @50 mA cm–2 and @100 mA cm–2) for seawater splitting. The results show that surface reconstruction of Ru2Co1BO-350 occurs during hydrogen evolution reaction and oxygen evolution reaction, which leads to the high activity and stability of the catalyst. The reconstructed surface is highly resistant to Cl– corrosion. The investigation suggests that a new …

At both conceptual and applied levels, quantum physics provides new opportunities as well as fundamental limitations. We hypothetically ask whether quantum games inspired by population dynamics can benefit from unique features of quantum mechanics such as entanglement and nonlocality. For doing so, we extend quantum game theory and demonstrate that in certain models inspired by ecological systems where several predators feed on the same prey, the strength of quantum entanglement between the various species has a profound effect on the asymptotic behavior of the system. For example, if there are sufficiently many predator species who are all equally correlated with their prey, they are all driven to extinction. Our results are derived in two ways: by analyzing the asymptotic dynamics of the system, and also by modeling the system as a quantum correlation network. The latter approach enables us to apply various tools from classical network theory in the above quantum scenarios. Several generalizations and applications are discussed.

This review describes the use of Electron Paramagnetic Resonance (EPR) to measure residue specific dynamics in proteins with a specific focus on Cu(II)‐based spin labels. First, we outline approaches used to measure protein motion by nitroxide‐based spin labels. Here, we describe conceptual details and outline challenges that limit the use of nitroxide spin labels to solvent‐exposed α‐helical sites. The bulk of this review showcases the use of newly developed Cu(II)‐based protein labels. In this approach, the strategic mutation of native residues on a protein to generate two neighboring Histidine residues (i.e., the dHis motif) is exploited to enable a rigid site‐selective binding of a Cu(II) complex. The chelation of the Cu(II) complex to dHis directly anchors the Cu(II) spin label to the protein backbone. The improvement in rigidity expands both the spin‐labeling toolkit as well as the resolution of many EPR …

[(LiNi0·8Co0·1Mn0.1)O2], or NCM811, a member of the LixNi1−y−zCoyMnzO2 (NCM) family of cathode active materials (CAMs), is gaining recognition in the battery community as the CAM of choice for future high energy density lithium-ion batteries, given its high nickel content of c. 80%. Yet, its commercialization is impeded by its mechanochemical instability at a high state of charge (SOC), which results in severe capacity fading and active lithium loss during cycling. In this contribution, we report conformal nanometer-thick (c. 4–7 nm) lithiated tin-oxide ternary coatings (LixSnyOz) deposited on NCM811 cathode powder using the atomic layer deposition (ALD) technique. The first-of-its-kind ALD coating, where Li is being accompanied by a second metal ion (Sn); provides a combination of benefits: (i) it stabilizes the crystal structure, (ii) suppresses electrode polarization, (iii) lowers the voltage hysteresis, and (iv …

Thermal effects are well known to influence the electronic and optical properties of materials through several physical mechanisms and are the basis for various optoelectronic devices. The thermo-optic (TO) effect - the refractive index variation with temperature (dn/dT), is one of the common mechanisms used for tunable optical devices, including integrated optical components, metasurfaces and nano-antennas. However, when a static and fixed operation is required, i.e., temperature invariant performance - this effect becomes a drawback and may lead to undesirable behavior through drifting of the resonance frequency, amplitude, or phase, as the operating temperature varies over time. In this work, we present a systematic approach to mitigate thermally induced optical fluctuations in nanophotonic devices. By using hybrid subwavelength resonators composed from two materials with opposite TO dispersions (dn/dT<0 and dn/dT>0), we are able to compensate for TO shifts and engineer meta-atoms and metasurfaces with zero effective TO coefficient (dn/dT~0). We demonstrate temperature invariant resonant frequency, amplitude, and phase response in meta-atoms and metasurfaces operating across a wide temperature range and broad spectral band. Our results highlight a path towards temperature invariant nanophotonics, which can provide constant and stable optical response across a wide range of temperatures and be applied to a plethora of optoelectronic devices. Controlling the sign and magnitude of TO dispersion extends the capabilities of light manipulation and adds another layer to the toolbox of optical engineering in nanophotonic …

Thermal effects are well known to influence the electronic and optical properties of materials through several physical mechanisms and are the basis for various optoelectronic devices. The thermo-optic (TO) effect-the refractive index variation with temperature (dn/dT), is one of the common mechanisms used for tunable optical devices, including integrated optical components, metasurfaces and nano-antennas. However, when a static and fixed operation is required, ie, temperature invariant performance-this effect becomes a drawback and may lead to undesirable behavior through drifting of the resonance frequency, amplitude, or phase, as the operating temperature varies over time. In this work, we present a systematic approach to mitigate thermally induced optical fluctuations in nanophotonic devices. By using hybrid subwavelength resonators composed from two materials with opposite TO dispersions (dn/dT< 0 …

The work reported herein discusses the improved electrochemical and thermal behavior of LiNi0.5Mn1.5O4 (LNMO) spinel cathodes via surface engineering using a series of zeolites. The limiting issues of these high voltage electrodes are phase transition during Li-ions intercalation/de-intercalation processes, weakening the active material's structure. Besides, it initiates harmful interfacial side reactions, including solution species oxidation and Ni & Mn dissolution, affecting their long-term cycling stability severely and detrimentally. Therefore, we propose a zeolite-based surface modification of LNMO involving a simple surface coating strategy that includes liquid-phase (ethanol) mixing followed by heat treatment at 200°C under nitrogen gas flow. The cathodes comprising LNMO coated with 2 wt% zeolites exhibited significantly improved cycling stability than the reference cathodes with the uncoated material …

Biosensors are analytical devices with a wide range of uses in various fields such as food, military, environmental monitoring, and clinical diagnostics. Similarly, polymers and their composites have sparked a lot of interest in biosensing because of their properties, including compatibility with biological molecules, efficient electron transfer during biochemical reactions, bioreagent loading, and biomolecule immobilization. Different nanoparticles such as carbon nanotubes, graphenes, gold nanoparticles, etc., have been efficiently integrated into the polymer matrix to improve performance features such as rapid response, high selectivity, improved sensitivity, long-term stability, and lower detection limit. Polymers in combination with nanomaterials provide a three-dimensional matrix that preserves biomolecule activity and provides an excellent platform for immobilization due to their good durability, porosity, selectivity …

A hydrothermal method was conducted to synthesize Ni(1−α)Co(α)MoO4 (α = 0, 0.1, 0.3, and 0.5 M) nanorods, which were proven as excellent electrode materials in a hybrid supercapacitor. Their electrochemical properties were also dependent on the Ni/Co ratio as demonstrated by different electrochemical techniques. Ni0.5Co0.5MoO4 (α = 0.5 M) offered specific capacity (Qg) = 354 Cg–1@1 Ag–1, a remarkable specific capacity with a notable retention capacity of 92% after 8000 repeated cycles at 10 Ag–1. Ni0.5Co0.5MoO4 with a high surface area outperformed the mono-metallic (NiMoO4) and bimetallic (Ni0.9Co0.1MoO4 and Ni0.7Co0.3MoO4) nanostructures. The hybrid supercapacitor (Ni0.5Co0.5MoO4//activated carbon) delivered a maximum Qcell of 53 Cg–1 at 1 Ag–1 with an energy density of 16.2 Wh kg–1 and power density of 725 W kg–1.

A distinguishing feature of ultracold collisions of bosonic lithium atoms is the presence of two near-degenerate two-body continua. The influence of such a near-degeneracy on the few-body physics in the vicinity of a narrow Feshbach resonance is investigated within the framework of a minimal model with two atomic continua and one closed molecular channel. The model allows analysis of the spin composition of loosely bound dimers and trimers. In the two-body sector the well-established coupled-channels calculations phenomenology of lithium is qualitatively reproduced, and its particularities are emphasized and clarified. In the three-body sector we find that the Efimov trimer energy levels follow a different functional form as compared to a single continuum scenario while the thresholds remain untouched. This three-channel model with two atomic continua complements our earlier developed three-channel model with two molecular channels [Y. Yudkin and L. Khaykovich, Phys. Rev. A 103, 063303 (2021)] and suggests that the experimentally observed exotic behavior of the first excited Efimov energy level [Y. Yudkin, R. Elbaz and L. Khaykovich, arXiv:2004.02723] is most probably caused by the short-range details of the interaction potential.

This review describes the use of Electron Paramagnetic Resonance (EPR) to measure residue specific dynamics in proteins with a specific focus on Cu(II)‐based spin labels. First, we outline approaches used to measure protein motion by nitroxide‐based spin labels. Here, we describe conceptual details and outline challenges that limit the use of nitroxide spin labels to solvent‐exposed α‐helical sites. The bulk of this review showcases the use of newly developed Cu(II)‐based protein labels. In this approach, the strategic mutation of native residues on a protein to generate two neighboring Histidine residues (i.e., the dHis motif) is exploited to enable a rigid site‐selective binding of a Cu(II) complex. The chelation of the Cu(II) complex to dHis directly anchors the Cu(II) spin label to the protein backbone. The improvement in rigidity expands both the spin‐labeling toolkit as well as the resolution of many EPR …

Being nearly unlimited natural resource containing mostly Na cations, the use of seawater as an electrolyte solution (aka seawater batteries) for electrochemical energy storage has received growing attention. To date, the vast majority of studies have focused on the use of seawater in Na-metal batteries protected by ion-conductive membranes hermetic to water. These systems, however, are complex and expensive, and suffer from a short cycling life. Here, we present alternative seawater batteries that utilize polyimide anodes. With its high capacity of more than 140 mAh/g, impressive rate capability, and excellent long-term stability (98% capacity retention after more than 9000 cycles), the prepared polyimide electrodes demonstrated to be promising candidate anodes for seawater electrochemical energy storage devices. Looking for a suitable cathode, we explored the use of nickel hexacyanoferrate (Ni-HCF) and …

Wilms’ tumors are pediatric malignancies that are thought to arise from faulty kidney development. They contain a wide range of poorly differentiated cell states resembling various distorted developmental stages of the fetal kidney, and as a result, differ between patients in a continuous manner that is not well understood. Here, we used three computational approaches to characterize this continuous heterogeneity in high-risk blastemal-type Wilms’ tumors. Using Pareto task inference, we show that the tumors form a triangle-shaped continuum in latent space that is bounded by three tumor archetypes with “stromal”,“blastemal”, and “epithelial” characteristics, which resemble the un-induced mesenchyme, the cap mesenchyme, and early epithelial structures of the fetal kidney. By fitting a generative probabilistic “grade of membership” model, we show that each tumor can be represented as a unique mixture of three hidden “topics” with blastemal, stromal, and epithelial characteristics. Likewise, cellular deconvolution allows us to represent each tumor in the continuum as a unique combination of fetal kidney-like cell states. These results highlight the relationship between Wilms’ tumors and kidney development, and we anticipate that they will pave the way for more quantitative strategies for tumor stratification and classification.