BINA

A deep learning network requires high-performance computer systems for solving complex problems with millions of parameters. In our lab, we develop a fully optical machine learning system that is based on the nonlinear four wave mixing process in multimode fibers. We exploit the optical nonlinear interactions between waves for developing a deep learning system faster than electronic based systems. finally, we resort to quantum light for realizing quantum deep learning system, which can bring the deep learning techniques to the quantum field. In this talk, we will present details of our novel system and discuss our preliminary results.

The unique fluorescent nanomaterials known as carbon dots (CDs) are highly resistant to photobleaching, have low toxicity, and are well soluble in water. Polyethyleneimine (PEI) coated CDs are a novel fluorophore with good biocompatibility and pH sensing ability. Here, p-phenylenediamine (p-PD) is used as a carbon source and hyperbranched PEI is used as a surface passivation agent in a simple, one-step hydrothermal synthesis process. The CDs optical characteristics are pH-responsive due to the presence of different amine groups on PEI, which is functional polycationic polymer. The limits of techniques based on fluorescence intensity can be overcome by fluorescent lifetime imaging microscopy (FLIM), a very sensitive method for detecting a microenvironment. In this study, FLIM was used to measure pH with pH-sensitive CDs. These molecules are nontoxic to the cells, and the positively charged CDs have …

Sending an ultrafast pulse in multimode fiber can lead to nonlinear interactions between the modes. When sending such a pulse in graded-index fibers there are cases where all the energy is transferring from the high-order modes into the lowest one. This effect is called modal self-cleaning. We developed a multimode time-lens, which measures the temporal and spatial dynamics of ultrafast signals in multimode fibers. With our system, we can detect the dynamics of each mode in time with high temporal resolution, and identify which mode is coupled to which and how the energy transfers between them. In this talk, We will present our measurement system in details and describe our novel results on modal self-cleaning. We will also comment on other multimode effects which our system can measure for the first time.

Geometry, an ancient yet vibrant branch of mathematics, has important and far-reaching impacts on various disciplines such as art, science, and engineering. Here, we introduce an emerging concept dubbed “geometric deep optical sensing” that is based on a number of recent demonstrations in advanced optical sensing and imaging, in which a reconfigurable sensor (or an array thereof) can directly decipher the rich information of an unknown incident light beam, including its intensity, spectrum, polarization, spatial features, and possibly angular momentum. We present the physical, mathematical, and engineering foundations of this concept, with particular emphases on the roles of classical and quantum geometry and deep neural networks. Furthermore, we discuss the new opportunities that this emerging scheme can enable and the challenges associated with future developments.

All‐solid‐state lithium batteries (ASSLBs) are considered as an alternative solution to lithium‐ion batteries, because of their safety and high theoretical energy density. Argyrodite‐based solid‐electrolytes (SEs), Li6PS5X (X = Cl, Cl0.5Br0.5 or Br), are promising candidates for ASSLBs. Most of the previous reports have used Li6PS5Cl as the default SE composition. Here, the electrochemical behavior of three different argyrodites with Cl− or Br−, or both, as the halogen is systematically studied. Using LiNi0.6Co0.2Mn0.2O2 as a model cathode, the behavior of these SEs in ASSLB cells is also studied. SEs containing Br show higher near‐room‐temperature ionic conductivity (>2 mS cm−1) and the critical current density (≥1 mA cm−2) during Li plating/stripping, and are stable up to 5 V versus Li/Li+. Li6PS5Br gives the best electrochemical performance in terms of C‐rate and long‐term cycling among the three …

We study the effects of electrostatic gating on the lateral distribution of charge carriers in two dimensional devices, in a non-linear dielectric environment. We compute the charge distribution using the Thomas-Fermi approximation to model the electrostatics of the system. The electric field lines generated by the gate are focused at the edges of the device, causing an increased depletion near the edges, compared to the center of the device. This effect strongly depends on the dimensions of the device, and the non-linear dielectric constant of the substrate. We experimentally demonstrate this effect using scanning superconducting interference device (SQUID) microscopy images of current distributions in gated LaAlO/SrTiO heterostructures.

Protection from viral infections depends on immunoglobulin isotype switching, which endows antibodies with effector functions. Here, we find that the protein kinase DYRK1A is essential for B cell-mediated protection from viral infection and effective vaccination through regulation of class switch recombination (CSR). Dyrk1a-deficient B cells are impaired in CSR activity in vivo and in vitro. Phosphoproteomic screens and kinase-activity assays identify MSH6, a DNA mismatch repair protein, as a direct substrate for DYRK1A, and deletion of a single phosphorylation site impaired CSR. After CSR and germinal center (GC) seeding, DYRK1A is required for attenuation of B cell proliferation. These findings demonstrate DYRK1A-mediated biological mechanisms of B cell immune responses that may be used for therapeutic manipulation in antibody-mediated autoimmunity.

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 wave packets 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 wave packets 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 some …

We present the first single-pair Bell inequality test, able to obtain a Bell parameter value for every entangled pair detected. After the measurements, each pair still presents a noteworthy amount of entanglement to be exploited for further quantum-protocols.

Fer and its sperm and cancer specific variant, FerT, are non-receptor tyrosine kinases which play roles in cancer progression and metastasis. Recent studies have shed light on the regulatory role of these kinases in ensuring proper sperm function. Comparison of the regulatory cascades in which Fer and FerT are engaged in sperm and cancer cells presents an interesting picture, in which similar regulatory interactions of these enzymes are integrated in a similar or different regulatory context in the two cell types. These diverse compositions extend from the involvement of Fer in modulation of actin cytoskeleton integrity and function, to the unique regulatory interactions of Fer with PARP-1 and the PP1 phosphatase. Furthermore, recent findings link the metabolic regulatory roles of Fer and FerT in sperm and cancer cells. In the current review, we discuss the above detailed aspects, which portray Fer and FerT as new regulatory links between sperm and malignant cells. This perspective view can endow us with new analytical and research tools that will deepen our understanding of the regulatory trajectories and networks that govern these two multi-layered systems.

Although direct methanol fuel cells (DMFCs) have been spotlighted in the past decade, their commercialization has been hampered by the poor efficiency of the methanol oxidation reaction (MOR) due to the unsatisfactory performance of currently available electrocatalysts. Herein, we developed a binder-free, copper-based, self-supported electrode consisting of a heterostructure of Cu3P and mixed copper oxides, i.e., cuprous–cupric oxide (Cu-O), as a high-performance catalyst for the electro-oxidation of methanol. We synthesized a self-supported electrode composed of Cu-O|Cu3P using a two-furnace atmospheric pressure–chemical vapor deposition (AP-CVD) process. High-resolution transmission electron microscopy analysis revealed the formation of 3D nanocrystals with defects and pores. Cu-O|Cu3P outperformed the MOR activity of individual Cu3P and Cu-O owing to the synergistic interaction between them. Cu3P|Cu-O exhibited a highest anodic current density of 232.5 mAcm−2 at the low potential of 0.65 V vs. Hg/HgO, which is impressive and superior to the electrocatalytic activity of its individual counterparts. The formation of defects, 3D morphology, and the synergistic effect between Cu3P and Cu-O play a crucial role in facilitating the electron transport between electrode and electrolyte to obtain the optimal MOR activity. Cu-O|Cu3P shows outstanding MOR stability for about 3600 s with 100% retention of the current density, which proves its robustness alongside CO intermediate.

The most abundant form of RNA editing in metazoa is the deamination of adenosines into inosines (A-to-I), catalyzed by ADAR enzymes. Inosines are read as guanosines by the translation machinery, and thus A-to-I may lead to protein recoding. The ability of ADARs to recode at the mRNA level makes them attractive therapeutic tools. Several approaches for Site-Directed RNA Editing (SDRE) are currently under development. A major challenge in this field is achieving high on-target editing efficiency, and thus it is of much interest to identify highly potent ADARs. To address this, we used the baker yeast Saccharomyces cerevisiae as an editing-naïve system. We exogenously expressed a range of heterologous ADARs and identified the hummingbird and primarily mallard-duck ADARs, which evolved at 40–42°C, as two exceptionally potent editors. ADARs bind to double-stranded RNA structures (dsRNAs), which in turn are temperature sensitive. Our results indicate that species evolved to live with higher core body temperatures have developed ADAR enzymes that target weaker dsRNA structures and would therefore be more effective than other ADARs. Further studies may use this approach to isolate additional ADARs with an editing profile of choice to meet specific requirements, thus broadening the applicability of SDRE.

The Aharonov-Bohm (AB) effect has been highly influential in fundamental and applied physics. Its topological nature commonly implies that an electron encircling a magnetic flux source in a field-free region must close the loop in order to generate an observable effect. In this Letter, we study a variant of the AB effect that apparently challenges this concept. The significance of weak values and nonlocal equations of motion is discussed as part of the analysis, shedding light on and connecting all these fundamental concepts.

Pancreatic ductal adenocarcinoma (PDA) is characterized by aggressive local invasion and metastatic spread, leading to high lethality. Although driver gene mutations during PDA progression are conserved, no specific mutation is correlated with the dissemination of metastases–. Here we analysed RNA splicing data of a large cohort of primary and metastatic PDA tumours to identify differentially spliced events that correlate with PDA progression. De novo motif analysis of these events detected enrichment of motifs with high similarity to the RBFOX2 motif. Overexpression of RBFOX2 in a patient-derived xenograft (PDX) metastatic PDA cell line drastically reduced the metastatic potential of these cells in vitro and in vivo, whereas depletion of RBFOX2 in primary pancreatic tumour cell lines increased the metastatic potential of these cells. These findings support the role of RBFOX2 as a potent metastatic suppressor in …

Bell inequalities are one of the cornerstones of quantum foundations, and fundamental tools for quantum technologies. Recently, the scientific community worldwide has put a lot of effort towards them, which culminated with loophole-free experiments. Nonetheless, none of the experimental tests so far was able to extract information on the full inequality from each entangled pair, since the wave function collapse forbids performing, on the same quantum state, all the measurements needed for evaluating the entire Bell parameter. We present here the first single-pair Bell inequality test, able to obtain a Bell parameter value for every entangled pair detected. This is made possible by exploiting sequential weak measurements, allowing to measure non-commuting observables in sequence on the same state, on each entangled particle. Such an approach not only grants unprecedented measurement capability, but also removes the need to choose between different measurement bases, intrinsically eliminating the freedom-of-choice loophole and stretching the concept of counterfactual-definiteness (since it allows measuring in the otherwise not-chosen bases). We also demonstrate how, after the Bell parameter measurement, the pair under test still presents a noteworthy amount of entanglement, providing evidence of the absence of (complete) wave function collapse and allowing to exploit this quantum resource for further protocols.

We report the observation of coherent oscillations in conversion efficiency of weakly bound dimers formed from a thermal gas of ultracold atoms. Finite thermal energy of the gas causes loss of coherence when a broad continuum is resonantly coupled to a discrete bound state. Restoration of the coherence can be achieved through nonadiabatic transitions of the dressed molecular energy level that are induced by a strong modulation pulse with fast envelope dynamics. Conditions to observe coherent oscillations are verified and control of their properties is demonstrated. The main experimental findings are supported by theoretical modeling and numerical calculations. The observed results may lead to a renewed interest in general studies of a discrete energy level coupled to a broadband continuum when the properties of both are fully controlled.

We review in this short perspective the history of cholesterol crystals and crystal structures. We address in particular the helical crystals that form in vitro and in pathology from environments rich in bile acids or from phospholipid membranes. We review the known mechanisms leading to crystals with chiral morphology, from screw‐dislocation mediated growth to mechanisms involving asymmetric mechanical strain. We propose a mechanism for cholesterol helical crystal development based on the monoclinic cholesterol monohydrate crystal structure. We suggest that curvature arises in few layers thick crystals due to the tension induced between the hydrophobic layer and the ice‐like H‐bonded lattice of the water molecules with the cholesterol hydroxy groups. Helicity would ensue through a combination of the curvature and the fast growth of a thin ribbon in one crystal direction.

Unconventional superconductivity was realized in systems comprising a monolayer of magnetic adatoms adsorbed on conventional superconductors, forming Shiba‐bands. Another approach to induce unconventional superconductivity and 2D Shiba‐bands was recently introduced, namely, by adsorbing chiral molecules (ChMs) on conventional superconductors, which act in a similar way to magnetic impurities as verified by conductance spectroscopy. However, the fundamental effect ChMs have on the strength of superconductivity has not yet been directly observed and mapped. In this work, local magnetic susceptometry is applied on heterostructures comprising islands of ChMs (α‐helix L‐polyalanine) monolayers adsorbed on Nb. It is found that the ChMs alter the superconducting landscape, resulting in spatially‐modulated weaker superconductivity. Surprisingly, the reduced diamagnetic response is located …

Disordered metallic nanostructures have features that are not realized in well‐defined nanometallic counterparts, such as broadband light localization and inhomogeneous refraction index at the nanoscale. Disordered metal systems with a networked inner architecture have both particles and voids with subwavelength dimensions which are randomly 3D organized in space. These disordered structures are benefited from high surface area and damage stability, permit guest materials permeability, and can be achieved in large scales employing less costs and expertise. Their abundant nanosize gaps and sharp tips can interact with incident light over a broadband range to generate a rich pattern of hot‐spots and can therefore function as an artificial leaf, for example. Here, the linear and nonlinear optical properties of both well‐defined and disordered plasmonic structures are reviewed with a focus on largescale 3D …

The advent of functional devices based on two-dimensional (2D) materials has further intensified the interest in the latter. However, the fabrication of structures using layered materials remains a key challenge. Recently, we proposed the so-called “Laser-Induced Transfer” method (LIT), as a digital and solvent-free approach for the high-resolution and intact transfer of 2D materials’ pixels. Here, we will further highlight the versatility of LIT by reporting results on the high-quality digital transfer of graphene and MoS2. These materials have emerged in the field of nanoelectronics, sensors and photonics due to their unique optoelectronic properties, but their high-quality transfer remains a hurdle. The quality of the transferred films has been confirmed with systematic characterization based on Scanning Electron Microscopy and Raman spectroscopy, as well as mobility’s extraction. Then we will present how the laser …

SwissSPAD3 is the latest of a family of widefield time-gated SPAD imagers developed for fluorescence lifetime imaging (FLI) applications. Its distinctive features are (i) the ability to define shorter gates than its predecessors (width W < 1 ns), (ii) support for laser repetition rates up to at least 80 MHz and (iii) a dual-gate architecture providing an effective duty cycle of 100%. We present widefield macroscopic FLI measurements of short lifetime NIR dyes, analyzed using the phasor approach. The results are compared with those previously obtained with SwissSPAD2 and to theoretical predictions.