BINA

The Aharonov-Bohm effect is a fundamental topological phenomenon with a wide range of applications. It consists of a charge encircling a region with a magnetic flux in a superposition of wavepackets having their relative phase affected by the flux. In this work, we analyze this effect using an entropic measure known as realism, originally introduced as a quantifier of a system's degree of reality and mathematically related to notions of global and local quantum coherence. More precisely, we look for observables that lead to gauge-invariant realism associated with the charge before it completes its loop. We find that the realism of these operators has a sudden change when the line connecting the center of both wavepackets crosses the solenoid. Moreover, we consider the case of a quantized magnetic field source, pointing out similarities and differences between the two cases. Finally, we discuss the implications of these results to the understanding of the effect.

In this work, we report a pixel reassignment based super-resolution reconstruction algorithm for structured illumination microscopy (entitled PR-SIM). PR-SIM provides a twofold theoretical resolution enhancement by reassigning the pixels in raw SIM images with respect to the center of each illumination fringe and applying further deconvolution. By comparing with frequency domain based algorithms, PR-SIM is more immune to fringe distortion and, hence, it is more suited for large-field SIM in that it processes the raw images locally. Meanwhile, the reconstruction speed of PR-SIM can be enhanced by skipping empty regions in the image and further enhanced by employing GPU-base parallel calculation. Overall, we can envisage that the PR-SIM can be extended for other illumination modulation based microscopic techniques.Optical microscopy is an indispensable imaging tool in many fields, yet its spatial …

The timing of cell division, and thus cell size in bacteria, is determined in part by the accumulation dynamics of the protein FtsZ, which forms the septal ring. FtsZ localization depends on membrane-associated Min proteins, which inhibit FtsZ binding to the cell pole membrane. Changes in the relative concentrations of Min proteins can disrupt FtsZ binding to the membrane, which in turn can delay cell division until a certain cell size is reached, in which the dynamics of Min proteins frees the cell membrane long enough to allow FtsZ ring formation. Here, we study the effect of Min proteins relative expression on the dynamics of FtsZ ring formation and cell size in individual Escherichia coli bacteria. Upon inducing overexpression of minE, cell size increases gradually to a new steady-state value. Concurrently, the time required to initiate FtsZ ring formation grows as the size approaches the new steady-state, at which point …

Magneto-optical imaging was employed to study dendritic flux avalanches in metal/superconductor and superconductor/superconductor hybrid structures over an extended range of magnetic field ramping rates. Our results in Cu/NbN show that the previously reported suppression of dendritic flux avalanches in metal coated superconducting films is limited to low ramping rates; as the ramping rate increases, the metal coating becomes less and less effective. A more complex behavior is exhibited in superconductor/superconductor hybrid structures. Our measurement in NbN partially coated with Nb, reveal three distinctive types of dendritic avalanches: those propagating in only one layer, either as regular dendrites in the uncoated NbN or as surface dendrites in the Nb layer, and hybrid dendrites that propagate in both the Nb and NbN layers simultaneously. These three types of dendrites are distinguished by their …

Increasing speeds of fiber-optics-based telecommunications, along with a large bandwidth of data processed in data centers, have focused attention on high-speed and bandwidth optical digital information processing. Optical processing requires high-density, high-speed, and low-power optical memory that can be integrated easily with planar semiconductor technology. The concept of optical memory has lent a novel perspective to optical domain data storage. We present our approach to creating nonvolatile optical memory based on the scattering field from gold nanoparticles. In our approach, data storage is based on the fabrication of gold nanoparticles in different spatial configurations. Reading of the stored data is achieved by analyzing the scattering image from each configuration.

Lead-acid systems dominate the global market owing to simple technology, easy fabrication, availability, and mature recycling processes. However, the sulfation of negative lead electrodes in lead-acid batteries limits its performance to less than 1000 cycles in heavy-duty applications. Incorporating activated carbons, carbon nanotubes, graphite, and other allotropes of carbon and compositing carbon with metal oxides into the negative active material significantly improves the overall health of lead-acid batteries. Carbons play a vital role in advancing the properties of lead-acid batteries for various applications, including deep depth of discharge cycling, partial state-of-charge, and high-rate partial state-of-charge cycling. Therefore, lead-carbon hybrid batteries and supercapacitor systems have been developed to enhance energy-power density and cycle life. This review article provides an overview of lead-acid …

One of the major issues in developing electrolyte solutions for rechargeable magnesium batteries is understanding the positive effect of chloride anions on Mg deposition-dissolution processes on the anode side, as well as intercalation-deintercalation of Mg2+ ions on the cathode side. Our previous results suggested that Cl- ions are adsorbed on the surface of Mg anodes and Chevrel phase MgxMo6S8 cathodes. This creates a surface add-layer that reduces the activation energy for the interfacial Mg ions transportation and related charge transfer, as well as promotes the transport of Mg2+ from the solution phase to the Mg anode surface and into the cathodes' host materials. Here, this work further examines the effect of adding chlorides to the state-of-the-art Mg[B(HFIP)4]2/DME electrolyte solution, specifically focusing on reversible magnesium deposition, as well as the performance of Mg cells with benchmark …

We present measurements of X-ray Parametric Down Conversion at the Advanced Photon Source synchrotron facility. We use an incoming pump beam at 22 keV to observe the simultaneous, elastic emission of down-converted photon pairs generated in a diamond crystal. The pairs are detected using high count rate silicon drift detectors with low noise. Production by down-conversion is confirmed by measuring time-energy correlations in the detector signal, where photon pairs within an energy window ranging from 10 to 12 keV are only observed at short time differences. By systematically varying the crystal misalignment and detector positions, we obtain results that are consistent with the constant total of the down-converted signal.

Raman spectroscopy in transition metal dichalcogenides (TMDCs) helps determine their structural information and layer dependency. Because it is non‐destructive and fast, it is an archetypal spectroscopic technique to investigate the structure and defects in TMDCs. In our earlier study, we used a metal‐dielectric coating to enhance Raman signal of WS2 because the Raman Spectra measured from WS2 coated on the standard Si/SiO2 was significantly lower. This metal‐dielectric coating allowed access to the otherwise unavailable E12g and A1g modes of WS2. In this study, we compare the Raman spectra of WS2 on a Si/SiO2 to that of metal layers (Au [200 nm] and Al [200 nm]). A significant enhancement in the Raman signal of 2‐3L WS2 is observed for both the Au and Al coatings. Although 200 nm Au coating enhances the Raman Signal better than the 10 nm Au coating, it does not resolve the other …

In adaptive immune receptor repertoire analysis, determining the germline variable (V) allele associated with each T- and B-cell receptor sequence is a crucial step. This process is highly impacted by allele annotations. Aligning sequences, assigning them to specific germline alleles, and inferring individual genotypes are challenging when the repertoire is highly mutated, or sequence reads do not cover the whole V region. Here, we propose an alternative naming scheme for the V alleles, as well as a novel method to infer individual genotypes. We demonstrate the strengths of the two by comparing their outcomes to other genotype inference methods. We validate the genotype approach with independent genomic long-read data. The naming scheme is compatible with current annotation tools and pipelines. Analysis results can be converted from the proposed naming scheme to the nomenclature determined …

Increasing speeds of fiber-optics-based telecommunications, along with a large bandwidth of data processed in data centers, have focused attention on high-speed and bandwidth optical digital information processing. Optical processing requires high-density, high-speed, and low-power optical memory that can be integrated easily with planar semiconductor technology. The concept of optical memory has lent a novel perspective to optical domain data storage. We present our approach to creating nonvolatile optical memory based on the scattering field from gold nanoparticles. In our approach, data storage is based on the fabrication of gold nanoparticles in different spatial configurations. Reading of the stored data is achieved by analyzing the scattering image from each configuration.

In this short review paper, relative evolution in time and related issues are analyzed within classical and quantum mechanics. We first discuss the basics of quantum frames of reference in both space and time. We then focus on the latter, and more specifically on the “timeless” approach to quantum mechanics due to Page and Wootters. We address time–energy uncertainty relations and the emergence of non-unitarity within this framework. We emphasize relational aspects of quantum time as well as unique features of non-inertial clock frames.

Diffusion occurs in numerous physical systems throughout nature, drawing its generality from the universality of the central limit theorem. Approximately a century ago it was realized that an extension to this type of dynamics can be obtained in the form of “anomalous” diffusion, where distributions are allowed to have heavy power-law tails. Owing to a unique feature of its momentum-dependent dissipative friction force, laser-cooled atomic ensembles can be used as a test bed for such dynamics. The interplay between laser cooling and anomalous dynamics bears deep predictive implications for fundamental concepts in both equilibrium and nonequilibrium statistical physics. The high degree of control available in cold-atom experiments allows for the parameters of the friction to be tuned, revealing transitions in the dynamical properties of the system. Rare events in both the momentum and spatial distributions are …

Stretched-exponential relaxation is a widely observed phenomenon found in glassy systems. It was previously modeled with non-Markovian dynamics reflecting a memory effect. Here, we study a Brownian particle under the influence of a confining, albeit weak, potential field that grows with distance as a sub-linear power law. We find that for this memoryless model, observables display stretched-exponential relaxation. The probability density function of the system is studied using a rate function ansatz. We obtain analytically the stretched-exponential exponent along with an anomalous power-law scaling of length with time. The rate function exhibits a point of nonanalyticity, indicating a dynamical phase transition. In particular, the rate function is double-valued both to the left and right of this point, leading to four different rate functions, depending on the choice of initial conditions and symmetry.

Synthesis of complex magnesium cations in ethereal solutions, is receiving a lot of attention due to their potential utilization in rechargeable magnesium batteries (RMB). The simplest complex cation, namely, solvated MgCl+, was hypothesized and reported as the most important cation in nonaqueous magnesium electrolyte solutions chemistry. However, such ions have never been isolated as the only cationic species in ethereal solutions developed for RMB. In this study, we report on successful isolation of the pure electrolyte MgCl(THF)5+- PhAlCl3, and on the electrochemical behavior of it in ethereal solutions. The structure of this compound was proved by single-crystal X-ray diffraction, Raman, and NMR spectroscopies. The novel MgCl(THF)5PhAlCl3/THF electrolyte solutions exhibit reversible Mg deposition/dissolution processes with anodic stability up to 2.7 V. The application of electrochemical cleaning pre …

In this work, we report a pixel reassignment based super-resolution reconstruction algorithm for structured illumination microscopy (entitled PR-SIM). PR-SIM provides a twofold theoretical resolution enhancement by reassigning the pixels in raw SIM images with respect to the center of each illumination fringe and applying further deconvolution. By comparing with frequency domain based algorithms, PR-SIM is more immune to fringe distortion and, hence, it is more suited for large-field SIM in that it processes the raw images locally. Meanwhile, the reconstruction speed of PR-SIM can be enhanced by skipping empty regions in the image and further enhanced by employing GPU-base parallel calculation. Overall, we can envisage that the PR-SIM can be extended for other illumination modulation based microscopic techniques.

First-passage time statistics in disordered systems exhibiting scale invariance are studied widely. In particular, long trapping times in energy or entropic traps are fat-tailed distributed, which slow the overall transport process. We study the statistical properties of the first-passage time of biased processes in different models, and we employ the big-jump principle that shows the dominance of the maximum trapping time on the first-passage time. We demonstrate that the removal of this maximum significantly expedites transport. As the disorder increases, the system enters a phase where the removal shows a dramatic effect. Our results show how we may speed up transport in strongly disordered systems exploiting scale invariance. In contrast to the disordered systems studied here, the removal principle has essentially no effect in homogeneous systems; this indicates that improving the conductance of a poorly …

Quantum many-body systems are emerging as key elements in the quest for quantum-based technologies and in the study of fundamental physics. In this context, finding control protocols that allow for fast and high fidelity evolutions across quantum phase transitions is of particular interest. Ideally, such controls should be scalable with the system size and not require controllable and unwanted extra interactions. In addition, its performance should be robust against potential imperfections. Here we design an invariant-based control technique that ensures perfect adiabatic-like evolution in the lowest energy subspace of the many-body system, and is able to meet all these requirements -- tuning the controllable parameter according to the analytical control results in high-fidelity evolutions operating close to the speed limit, valid for any number particles. As such, Kibble-Zurek scaling laws break down, leading to tunable and much better time scaling behavior. We illustrate our findings by means of detailed numerical simulations in the transverse-field Ising and long-range Kitaev models and demonstrate the robustness against noisy controls and disorder.

The transition from dissolution-precipitation to quasi-solid-state sulfur reaction promises restricted polysulfide shuttle and lean electrolyte operation of Li-S batteries but incurs poor reaction kinetics. We here demonstrate that structural reorganization of sparingly solvating electrolytes (SSEs)—which is uniquely afforded by using low-density and low-cost aromatic anti-solvents—is vital for taming the quasi-solid-state sulfur reaction. Aromatic anti-solvents disrupt the interconnected structure of concentrated tetrahydrofuran (THF) electrolyte, uniquely creating subdomains that act to dissolve elemental sulfur, thus accelerating its consumption and re-formation while maintaining ultralow polysulfides solubility. The altered subdomains further result in robust solid electrolyte interphase (SEI) on lithium metal. As a result, the Li-S cell with a 3 mgsulfur cm−2 sulfur cathode can cycle steadily for ∼160 cycles with a lean …

Despite significant advancements in in vitro cardiac modeling approaches, researchers still lack the capacity to obtain in vitro measurements of a key indicator of cardiac function: contractility, or stroke volume under specific loading conditions—defined as the pressures to which the heart is subjected prior to and during contraction. This work puts forward a platform that creates this capability, by providing a means of dynamically controlling loading conditions in vitro. This dynamic tissue loading platform consists of a thin magnetoresponsive hydrogel cantilever on which 2D engineered myocardial tissue is cultured. Exposing the cantilever to an external magnetic field—generated by positioning magnets at a controlled distance from the cantilever—causes the hydrogel film to stretch, creating tissue load. Next, cell contraction is induced through electrical stimulation, and the force of the contraction is recorded, by …

Fermi liquids respond differently to perturbations depending on whether their frequency is higher (collisionless regime) or lower (hydrodynamic regime) than the interparticle collision rate. This results in a different phase velocity between the collisionless zero sound and the hydrodynamic first sound. We performed terahertz photocurrent nanoscopy measurements on graphene devices, with a metallic gate close to the graphene layer, to probe the dispersion of propagating acoustic plasmons, the counterpart of sound modes in electronic Fermi liquids. We report the observation of a change in the plasmon phase velocity when the excitation frequency approaches the electron-electron collision rate that is compatible with the transition between the zero and the first sound mode.