BINA

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 …

We propose and demonstrate a holographic imaging scheme exploiting random illuminations for recording hologram and then applying numerical reconstruction and twin removal. We use an in-line holographic geometry to record the hologram in terms of the second-order correlation and apply the numerical approach to reconstruct the recorded hologram. The twin image issue of the in-line holographic scheme is resolved by an unsupervised deep learning(DL) based method using an auto-encoder scheme. This strategy helps to reconstruct high-quality quantitative images in comparison to the conventional holography where the hologram is recorded in the intensity rather than the second-order intensity correlation. Experimental results are presented for two objects, and a comparison of the reconstruction quality is given between the conventional inline holography and the one obtained with the proposed technique.

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.

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.

Perovskite photovoltaics offer a highly efficient and low-cost solar energy harvesting technology. However, the presence of lead (Pb) cations in photovoltaic halide perovskite (HaPs) materials is concerning, and quantifying the environmental hazard of accidental Pb2+ leaching into the soil is crucial for assessing the sustainability of this technology. Pb2+ from inorganic salts was previously found to remain in the upper soil layers due to adsorption. However, Pb-HaPs contain additional organic and inorganic cations, and competitive cation adsorption may affect Pb2+ retention in soils. Therefore, we measured, analyzed by simulations and report the depths to which Pb2+ from HaPs penetrates into 3 types of agricultural soil. Most of the HaP-leached Pb2+ is found to be retained already in the first cm of the soil columns, and subsequent rain events do not induce Pb2+ penetration below the first few cm of soil surface …

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 …

A novel technology for the precise fabrication of quartz resonators for MEMS applications is introduced. This approach is based on the laser-induced chemical etching of quartz. The main processing steps include femtosecond UV laser treatment of a Cr-Au-coated Z-cut alpha quartz wafer, followed by wet etching. The laser-patterned Cr-Au coating serves as an etch mask and is used to form electrodes for piezoelectric actuation. This fabrication approach does not alter the quartz’s crystalline structure or its piezo-electric properties. The formation of defects, which is common in laser micromachined quartz, is prevented by optimized process parameters and by controlling the temporal behavior of the laser-matter interactions. The process does not involve any lithography and allows for high geometric design flexibility. Several configurations of piezoelectrically actuated beam-type resonators were fabricated using …

Rapid, highly sensitive, and high-throughput detection of biomarkers at low concentrations is invaluable for early diagnosis of various diseases. In many sensitive immunoassays the protocol is time consuming and requires a complicated and expensive detection system. Here, we demonstrate a high-throughput optical modulation biosensing (ht-OMB) system, which enables reading a 96-well plate within 10 minutes. Using the system, to detect human Interleukin-8, we demonstrated a limit of detection of 0.14 ng/L and a 4-log dynamic range. Testing 94 RNA extracts from 36 confirmed RT-qPCR SARS-CoV-2-positive patients (C_t≤40) and 58 confirmed RT-qPCR SARS-CoV-2-negative individuals resulted in 100% sensitivity and 100% specificity.

In many industrial settings, films of polymers such as polypropylene (PP) and polyethylene terephthalate (PET) require surface treatment due to poor wettability and low surface energy. Here, a simple process is presented to prepare durable thin coatings composed of polystyrene (PS) core, PS/SiO2 core–shell, and hollow SiO2 micro/nanoparticles onto PP and PET films as a platform for various potential applications. Corona-treated films were coated with a monolayer of PS microparticles by in situ dispersion polymerization of styrene in ethanol/2-methoxy ethanol with polyvinylpyrrolidone as stabilizer. A similar process on untreated polymeric films did not yield a coating. PS/SiO2 core–shell coated microparticles were produced by in situ polymerization of Si(OEt)4 in ethanol/water onto a PS-coated film, creating a raspberry-like morphology with a hierarchical structure. Hollow porous SiO2-coated microparticles onto …

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.

We demonstrate that the direction of current rectification via one of nature’s most efficient light-harvesting systems, the photosystem 1 complex (PS1), can be controlled by its orientation on Au substrates. Molecular self-assembly of the PS1 complex using four different linkers with distinct functional head groups that interact by electrostatic and hydrogen bonds with different surface parts of the entire protein PS1 complex was used to tailor the PS1 orientation. We observe an orientation-dependent rectification in the current–voltage characteristics for linker/PS1 molecule junctions. Results of an earlier study using a surface two-site PS1 mutant complex having its orientation set by covalent binding to the Au substrate supports our conclusion. Current–voltage–temperature measurements on the linker/PS1 complex indicate off-resonant tunneling as the main electron transport mechanism. Our ultraviolet photoemission …

CdS nanoparticles were introduced on E. coli cells to construct a hydrogen generating biohybrid system via the biointerface of tannic acid‐Fe complex. This hybrid system promotes good biological activity in a high salinity environment. Under light illumination, the as‐synthesized biohybrid system achieves a 32.44 % enhancement of hydrogen production in seawater through a synergistic effect.

While great progress has been achieved in developing optical methods for measuring fast changes in membrane potential (like action potentials) in excitable cells, less progress has been made in precise (and calibrated) measurements of steady state resting membrane potentials (RMPs) and small changes in RMPs (in excitable or non-excitable cells). In excitable cells, small changes in RMPs are associated with multiple physiological processes such as sub-threshold events in neuronal signaling and in synaptic plasticity. They also play an important role in cell differentiation and proliferation of cardiomyocytes. In non-excitable cells, such as bacterial colonies, RMP changes play important roles in intercellular communication, coordination, metabolism, and stress response. Accurate and precise recordings of minute RMP changes require noise-immune optical tools. We have been developing an RMP (calibrated …

During reproduction, male and female flies use wing vibration to generate different acoustic signals. Males produce a courtship song before copulation that is easily recognized by unilateral wing vibration. In copula, females produce a distinct sound pattern (copulation song) with both wings. Sexual rejection of immature virgins and aggressive encounters between males are also accompanied by sound pulses generated by wing flicks. Fly song has frequency ranges audible to the human ear and can be directly listened to after appropriate amplification. When displayed in an oscillogram, audio recordings can be mapped on wing-movement patterns and thus provide a fast and precise method to sample and quantify motor behaviors with high temporal resolution. After recording different fly sounds, their effect on behavior can be tested in playback experiments.

Extensive research work has been invested in the past decade in finding replacements for platinum-based electrocatalysts for the oxygen reduction reaction in fuel cells. The majority of these alternative electrocatalysts are based on transition-metal ions coordinated by organic ligands. Different from previously reported approaches for electrocatalysts, we describe here the synthesis, characterization, and oxygen reduction reaction activity of lanthanide complex electrocatalyst with ytterbium as the metal center. A metal–organic framework of Yb and benzene tricarboxylic acid as a ligand was synthesized on activated carbon (Yb(III)BTC@AC) to achieve electrical conductivity in a procedure similar to M-BTC@AC electrocatalysts with transition-metal centers. The Yb complex in activated carbon presents oxygen reduction reaction activity in alkaline solution with high onset potential relative to other nonpyrolyzed …

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.

Metal-nitrogen-carbons (M-N-Cs) as a reliable substitution for platinum-group-metals (PGMs) for oxygen reduction reaction (ORR) are emerging candidates to rationalize the technology of fuel cells. The development of M-N-Cs can further be economized by consuming waste biomass as an inexpensive carbon source for the electrocatalyst support. Herein, we report the simple fabrication and in-depth characterization of electrocatalysts using lignin-derived activated char. The activated char (LAC) was functionalized with metal phthalocyanine (FePc and MnPc) via atmosphere-controlled pyrolysis to produce monometallic M-N-Cs (L_Mn and L_Fe) and bimetallic M1-M2-N-Cs (L_FeMn) electrocatalysts. Raman spectroscopy and transmission electron microscopy (TEM) revealed a defect-rich architecture. XPS confirmed the coexistence of various nitrogen-containing active moieties. L_Fe and L_FeMn demonstrated …

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.

Courtship in Drosophila melanogaster involves a series of innate, complex behaviors that allow male and female flies to exchange sensory information and assess the quality of a potential mate. Although highly robust and stereotypical, courtship behaviors can be modulated by internal state and experience. This protocol describes methods for designing and carrying out experiments that measure courtship performance in single-pair assays, in which a male is paired with a female, or in competitive assays, in which a male is presented with a female and with a male competitor. It also includes approaches for measuring female sexual receptivity during courtship.

Cold atoms hold much promise for the realization of quantum technologies, but still encounter many challenges. In this work we show how the fundamental Casimir-Polder force, by which atoms are attracted to a surface, may be temporarily suppressed by utilizing a specially designed quantum potential, which is familiar from the hydrodynamic or Bohmian reformulations of quantum mechanics. We show that when harnessing the quantum potential via suitable atomic wave-packet engineering, the absorption by the surface can be dramatically reduced. As a result, the probing time of the atoms as sensors can increase. This is proven both analytically and numerically. Furthermore, an experimental scheme is proposed for achieving the required shape for the atomic wave packet. All these may assist existing applications of cold atoms in metrology and sensing and may also enable prospective ones. Finally, these …

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 …