TAU Nanocenter

We propose to use free-electrons as quantum probes of strongly coupled light-matter systems. Interactions with such systems are distinctly imprinted on the electron energy spectrum, allowing for quantum detection and new photon blockade mechanisms.

We study theoretically and observe experimentally the evolution of periodic wave trains by utilizing surface gravity water wave packets. Our experimental system enables us to observe both the amplitude and the phase of these wave packets. For low steepness waves, the propagation dynamics is in the linear regime, and these waves unfold a Talbot carpet. By increasing the steepness of the waves and the corresponding nonlinear response, the waves follow the Akhmediev breather solution, where the higher frequency periodic patterns at the fractional Talbot distance disappear. Further increase in the wave steepness leads to deviations from the Akhmediev breather solution and to asymmetric breaking of the wave function. Unlike the periodic revival that occurs in the linear regime, here the wave crests exhibit self acceleration, followed by self deceleration at half the Talbot distance, thus completing a smooth …

In this study, the extraordinary biosorption of mucin, a natural glycoprotein with selectivity towards metals in physiological processes, is leveraged to remove heavy metals from wastewater. The authors assess the performance of dissolved mucin for Hg2+ adsorption through studies of kinetics, capacity, and selectivity. The results show that mucin can adsorb more than 124 mg g−1 Hg2+ while exhibiting ultra‐fast kinetics, with an equilibrium reached in a few seconds. The adsorption levels are optimized in pHs higher than 4 and remain almost unchanged in the presence of background ions. X‐ray photoelectron spectroscopy and Fourier transform infrared analyses indicated that the sorption mechanism is dominated by electrostatic interactions and mercuric complexation with mucin's active sites, whereas the undesirable removal via mercuric reduction does not occur. To use mucin in a practical and green fashion for …

We investigate bright and dark diffractive focusing emerging in the free propagation of specific wave profiles. These general wave phenomena manifest themselves in matter, water, and classical waves. In this article, we lay the foundations for these effects and illustrate their origin in Wigner phase space. Our theoretical studies are supported by experimental demonstrations of dark focusing in water waves. Moreover, by using different phase slits we analyze several aspects of bright and dark focusing for classical and matter waves.

The growing in manufacturing and applications of graphene oxide (GO), a two-dimensional nanomaterial, highlights the need for a better understanding of its environmental impact and toxicity. This work investigates the interaction of GO with cell membrane models as an indication for GO's potential harmfulness. A wide range of biologically-relevant membrane parameters (size, charge and, cholesterol content) and simple optical techniques were used to evaluate the outcome of interactions of vesicular cell membrane models with GO. Loss of membrane integrity was found to be positively correlated with electrostatic attraction and negatively correlated with cholesterol content. The size of vesicle-GO aggregates increased as a function of initial vesicle size, while cholesterol content was found to have a negligible effect on aggregation. Interestingly, charged vesicles reduced vesicle-GO aggregate size either by …

This comment on the paper by Karlovets and Pupasov-Maksimov [Phys. Rev. A 103, 012214 (2021)] addresses their criticism of the combined experimental and theoretical study by Remez et al.[Phys. Rev. Lett. 123, 060401 (2019)]. We show, by means of simple optical arguments as well as numerical simulations, that the arguments raised by Karlovets and Pupasov-Maksimov do not hold in the experimental regime reported by Remez et al. Further, we discuss a clarification for the theoretical derivations presented by Karlovets and Pupasov-Maksimov, as they hold only when the final state of the emitting electron is observed in coincidence with the emitted photon. Although this scenario is feasible and may stimulate new experimental regimes that do correspond to the predictions reported by Karlovets and Pupasov-Maksimov, it is not the common scenario in cathodoluminescence, where only the light is measured …

Intracellular recording of action potentials is an essential mean for studying disease mechanisms, and for electrophysiological studies, particularly in excitable cells as cardiomyocytes or neurons. Current strategies to obtain intracellular recordings include three-dimensional (3D) nanoelectrodes that can effectively penetrate the cell membrane and achieve high-quality intracellular recordings in a minimally invasive manner, or transient electroporation of the membrane that can yield temporary intracellular access. However, the former strategy requires a complicated and costly fabrication process, and the latter strategy suffers from high dependency on the method of application of electroporation, yielding inconsistent, suboptimal recordings. These factors hinder the high throughput use of these strategies in electrophysiological studies. In this work, we propose an advanced cell-based biosensing platform that relies on …

High levels of persistent contaminants such as microplastics (MPs) and trace organic compounds (TrOCs) in the aquatic environment have become a major threat on the ecosystem and human health. While MP's role as a vector of environmental TrOCs is widely discussed in the literature, the corresponding implications of the interaction between these two compounds on human health (i.e., their joint toxic effect) have not been illustrated. Using a TrOCs model (Triclosan, TCS) and primary MPs (polystyrene microbeads), this work evaluates the sorption and desorption potential of TCS and MPs in simulated environmental and cellular conditions, respectively, and estimates the single and joint toxicity of these interactions toward human cells (Caco-2). Surface functionality of the microbeads highly increased their adsorption capacity of TCS, from 2.3 mg TCS for non−functionalized microbeads to 4.6 mg and 6.1 mg TCS …

Successfully engineering a functional, human, myocardial pump would represent a therapeutic alternative for the millions of patients with end-stage heart disease and provide an alternative to animal-based preclinical models. Although the field of cardiac tissue engineering has made tremendous advances, major challenges remain, which, if properly resolved, might allow the clinical implementation of engineered, functional, complex 3D structures in the future. In this Review, we provide an overview of state-of-the-art studies, challenges that have not yet been overcome and perspectives on cardiac tissue engineering. We begin with the most clinically relevant cell sources used in this field and discuss the use of topological, biophysical and metabolic stimuli to obtain mature phenotypes of cardiomyocytes, particularly in relation to organized cytoskeletal and contractile intracellular structures. We then move from the …

While molybdenum disulfide (MoS2) nanosheets have demonstrated selective and efficient adsorption potential toward heavy metals, there are still many barriers-such as nanomaterial practicality, safety, and sustainability-to nanomaterials' large-scale application in water treatment schemes. For example, nano-MoS2 has been shown to take part in redox reactions during heavy metal recovery (which deteriorates the active nanomaterial) and can release molybdenum to the treated water. This study addresses these barriers through the bottom-up hydrothermal synthetic growth of MoS2 onto granular activated carbon (AC) as an active adsorbing platform. Not only does this strategic design avoid redox reactions, but it also largely immobilizes MoS2 to a substrate, which mitigates nanomaterial loss to solution and enables facile recovery of the nanomaterial after use. The hybrid adsorbent (MoS2@AC) was extensively …

The geometric phase of light has been demonstrated in various platforms of the linear optical regime, raising interest both for fundamental science as well as applications, such as flat optical elements. Recently, the concept of geometric phases has been extended to nonlinear optics, following advances in engineering both bulk nonlinear photonic crystals and nonlinear metasurfaces. These new technologies offer a great promise of applications for nonlinear manipulation of light. In this review, we cover the recent theoretical and experimental advances in the field of geometric phases accompanying nonlinear frequency conversion. We first consider the case of bulk nonlinear photonic crystals, in which the interaction between propagating waves is quasi-phase-matched, with an engineerable geometric phase accumulated by the light. Nonlinear photonic crystals can offer efficient and robust frequency conversion in …

Cell therapy using induced pluripotent stem cell‐derived neurons is considered a promising approach to regenerate the injured spinal cord (SC). However, the scar formed at the chronic phase is not a permissive microenvironment for cell or biomaterial engraftment or for tissue assembly. Engineering of a functional human neuronal network is now reported by mimicking the embryonic development of the SC in a 3D dynamic biomaterial‐based microenvironment. Throughout the in vitro cultivation stage, the system's components have a synergistic effect, providing appropriate cues for SC neurogenesis. While the initial biomaterial supported efficient cell differentiation in 3D, the cells remodeled it to provide an inductive microenvironment for the assembly of functional SC implants. The engineered tissues are characterized for morphology and function, and their therapeutic potential is investigated, revealing improved …

Biofouling is a multifaceted and unavoidable problem in the application of membrane separation technology. Here, we functionalized polyvinylidene fluoride (PVDF) ultrafiltration membranes with poly(ionic liquid) (PIL) brushes to provide them with antibiofouling properties. The PIL brush grafted membranes (PIL-M) were prepared via atom transfer radical polymerization (ATRP) using different ionic liquids (ILs) on the membrane surface. Four functionalized membranes with different alkyl chain lengths (C4-M, C8-M, C12-M, and C16-M) were prepared to explore the relationship between surface structure and antibacterial properties. Our results showed that all of the PIL-M had antibacterial capabilities with the highest efficiency of 84.6% for the C12-M. Moreover, the antibacterial performance was improved by increasing the ATRP reaction temperature and time. Liposome vesicles were used as the bacterial cell …

Spatial modes of light can be used as carriers of information in classical optical communication or as an alphabet in quantum optical communication. In order to exploit the spatial domain, it is required to (de)multiplex different modes from a shared input channel into different output ports. Mode sorters have been employed in free-space and fiber systems but to date have not been realized for planar guided waves. Here we present a general method for compact on-chip sorting of different planar beams with a micrometric footprint and nanometric thickness. The designs were generated using a linkage-tree-based genetic algorithm and were experimentally demonstrated on a surface plasmon polariton platform by sorting of Hermite–Gaussian beams. The method used here can be readily applied to optimize complex, large-scale optical devices involving beam propagation methods.

In this study, the extraordinary biosorption of mucin, a natural glycoprotein with selectivity towards metals in physiological processes, is leveraged to remove heavy metals from wastewater. The authors assess the performance of dissolved mucin for Hg2+ adsorption through studies of kinetics, capacity, and selectivity. The results show that mucin can adsorb more than 124 mg g−1 Hg2+ while exhibiting ultra‐fast kinetics, with an equilibrium reached in a few seconds. The adsorption levels are optimized in pHs higher than 4 and remain almost unchanged in the presence of background ions. X‐ray photoelectron spectroscopy and Fourier transform infrared analyses indicated that the sorption mechanism is dominated by electrostatic interactions and mercuric complexation with mucin's active sites, whereas the undesirable removal via mercuric reduction does not occur. To use mucin in a practical and green fashion for …

We design, fabricate and characterize integrated mode sorters for multimode fibers that guide well-separated vortex modes. We use 3D-direct laser printing to print a collimator and a Cartesian to log-polar mode transformer on the tip of the fiber. This polarization insensitive device can send different modes into different exit angles and is therefore useful for space division multiplexed optical communication. Two types of fibers with two corresponding sorters were used, enabling to sort either 4 or 8 different modes in a compact and robust manner. The integration of the vortex fiber and multiplexer opens the door for widespread exploitation of OAM for data multiplexing in fiber networks. http://dx. doi. org/10.1364/OL. 99.099999

While molybdenum disulfide (MoS2) nanosheets have demonstrated selective and efficient adsorption potential toward heavy metals, there are still many barriers—such as nanomaterial practicality, safety, and sustainability—to nanomaterials’ large-scale application in water treatment schemes. For example, nano-MoS2 has been shown to take part in redox reactions during heavy metal recovery (which deteriorates the active nanomaterial) and can release molybdenum to the treated water. This study addresses these barriers through the bottom-up hydrothermal synthetic growth of MoS2 onto granular activated carbon (AC) as an active adsorbing platform. Not only does this strategic design avoid redox reactions, but it also largely immobilizes MoS2 to a substrate, which mitigates nanomaterial loss to solution and enables facile recovery of the nanomaterial after use. The hybrid adsorbent (MoS2@AC) was …

Mercury (Hg) contamination in groundwater has been recognized as a serious threat to human health and ecological systems all over the world. This study demonstrated that two-dimensional (2D) molybdenum disulfide (MoS2) nanosheets can efficiently remove Hg in groundwater, with high Hg uptake capacity, ultrafast removal kinetics, and excellent selectivity. Interestingly, we found that the groundwater matrix has profound implications on the Hg removal efficiency and mechanisms by MoS2 nanosheets. Specifically, surface adsorption is the dominant removal mechanism for Hg in DI water owing to the high affinity between Hg(II) and MoS2via strong Lewis acid/base soft–soft interactions. In groundwater, however, the presence of Cl− renders HgClOH the dominant species, which can undergo adsorption onto MoS2 and homolytic cleavage to form the˙HgCl radical. As an intermediate radical, ˙HgCl could either …

Mercury (Hg) contamination in groundwater has been recognized as a serious threat to human health and ecological systems all over the world. This study demonstrated that two-dimensional (2D) molybdenum disulfide (MoS2) nanosheets can efficiently remove Hg in groundwater, with high Hg uptake capacity, ultrafast removal kinetics, and excellent selectivity. Interestingly, we found that the groundwater matrix has profound implications on the Hg removal efficiency and mechanisms by MoS2 nanosheets. Specifically, surface adsorption is the dominant removal mechanism for Hg in DI water owing to the high affinity between Hg(II) and MoS2 via strong Lewis acid/base soft–soft interactions. In groundwater, however, the presence of Cl− renders HgClOH the dominant species, which can undergo adsorption onto MoS2 and homolytic cleavage to form the˙HgCl radical. As an intermediate radical, ˙HgCl could either …

Potable reuse of municipal wastewater is often the lowest-energy option for increasing the availability of fresh water. However, limited data are available on the energy consumption of potable reuse facilities and schemes, and the many variables affecting energy consumption obscure the process of estimating energy requirements. By synthesizing available data and developing a simple model for the energy consumption of centralized potable reuse schemes, this study provides a framework for understanding when potable reuse is the lowest-energy option for augmenting water supply. The model is evaluated to determine a representative range for the specific electrical energy consumption of direct and indirect potable reuse schemes and compare potable reuse to other water supply augmentation options, such as seawater desalination. Finally, the model is used to identify the most promising avenues for further …