Center for Nanoscience and Nanotechnology

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Nov 2024 • Journal of Colloid and Interface Science

A self-standing superhydrophobic material formed by the self-assembly of an individual amino acid

Tan Hu, Zhuo Zhang, Meital Reches

HypothesisThere is a growing interest in designing superhydrophobic materials for many applications including self-clean surfaces, separation systems, and antifouling solutions. Peptides and amino acids offer attractive building blocks for these materials since they are biocompatible and biodegradable and can self-assemble into complex ordered structures.Experiments and SimulationsWe designed a self-standing superhydrophobic material through the self-assembly of an individual functionalized aromatic amino acid, Cbz-Phe(4F). The self-assembly of Cbz-Phe(4F) was investigated by experimental and computational methods. Moreover, when drop-casted three times on a solid support, it formed a self-standing superhydrophobic material. The mechanical properties and chemical stability of this self-standing superhydrophobic material were demonstrated.FindingsThe designed Cbz-Phe(4F) self-assembled into …

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May 2024 • Advanced Optical Materials 12 (4), 2301612, 2024

Silicon Rich Nitride Huygens Metasurfaces in the Visible Regime

Oren Goldberg, Rivka Gherabli, Jinan Nijem, Noa Mazurski, Uriel Levy

We experimentally demonstrate a Huygens metasurface in the visible regime utilizing Silicon rich Nitride (SRN). Offering high refractive index and CMOS compatibility, SRN is an outstanding candidate to replace the widely used TiO2.

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Apr 2024 • Plant and Soil

Studying tomato brown rugose fruit virus longevity in soil and virion susceptibility to pH treatments helped improve virus control by soil disinfection

Ori Molad, Elisheva Smith, Neta Luria, Elena Bakelman, Oded Lachman, Meital Reches, Aviv Dombrovsky

MethodsToBRFV longevity in naturally-contaminated soil was tested by collecting an earth pile after a growth-cycle of ToBRFV-infected tomato plants. The soil was sampled at different time points and root-truncated tomato seedlings were planted. Virion stability at a range of pH values was determined by testing virus infectivity on Nicotiana glutinosa; by amplifying large genome segments using RT-PCR; and by transmission electron microscopy (TEM) visualization.ResultsToBRFV-infectivity in naturally-contaminated soil was profoundly reduced by day 184 of pile-age and was abolished between 205 and 385 days of pile-age. Virion stability and genome integrity were preserved over the pH range of 2-10. At pH 1, ToBRFV-infectivity and efficiency of large genome segment amplifications were reduced. At pH values above 10, modified particle morphologies were visualized by TEM, and virus infectivity was abolished …

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Apr 2024 • The Journal of Chemical Physics

Seeing is believing: Correlating optoelectronic functionality with atomic scale imaging of single semiconductor nanocrystals

Yonatan Ossia, Adar Levi, Nadav Chefetz, Amir Peleg, Sergei Remennik, Atzmon Vakahi, Uri Banin

A unique on-chip method for the direct correlation of optical properties, with atomic-scale chemical–structural characteristics for a single quantum dot (QD), is developed and utilized in various examples. This is based on performing single QD optical characterization on a modified glass substrate, followed by the extraction of the relevant region of interest by focused-ion-beam–scanning electron microscope processing into a lamella for high resolution scanning transmission electron microscopy (STEM) characterization with atomic scale resolution. The direct correlation of the optical response under an electric field with STEM analysis of the same particle allows addressing several single particle phenomena: first, the direct correlation of single QD photoluminescence (PL) polarization and its response to the external field with the QD crystal lattice alignment, so far inferred indirectly; second, the identification of unique …

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Apr 2024 • Biosensors

Enhanced Detection of Estrogen-like Compounds by Genetically Engineered Yeast Sensor Strains

Nidaa Abu-Rmailah, Liat Moscovici, Carolin Riegraf, Hadas Atias, Sebastian Buchinger, Georg Reifferscheid, Shimshon Belkin

The release of endocrine-disrupting compounds (EDCs) to the environment poses a health hazard to both humans and wildlife. EDCs can activate or inhibit endogenous endocrine functions by binding hormone receptors, leading to potentially adverse effects. Conventional analytical methods can detect EDCs at a high sensitivity and precision, but are blind to the biological activity of the detected compounds. To overcome this limitation, yeast-based bioassays have previously been developed as a pre-screening method, providing an effect-based overview of hormonal-disruptive activity within the sample prior to the application of analytical methods. These yeast biosensors express human endocrine-specific receptors, co-transfected with the relevant response element fused to the specific fluorescent protein reporter gene. We describe several molecular manipulations of the sensor/reporter circuit in a Saccharomyces cerevisiae bioreporter strain that have yielded an enhanced detection of estrogenic-like compounds. Improved responses were displayed both in liquid culture (96-well plate format) as well as in conjunction with sample separation using high-performance thin-layer chromatography (HPTLC). The latter approach allows for an assessment of the biological effect of individual sample components without the need for their chemical identification at the screening stage.

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Mar 2024 • Physical Review Research

Signature of long-ranged spin triplets across a two-dimensional superconductor/helimagnet van der Waals interface

A Spuri, D Nikolić, S Chakraborty, M Klang, H Alpern, O Millo, H Steinberg, W Belzig, E Scheer, A Di Bernardo

The combination of a superconductor with a magnetically inhomogeneous material has been established as an efficient mechanism for the generation of long-ranged spin-polarized (spin-triplet) Cooper pairs. Evidence for this mechanism, however, has been demonstrated based on studies done on thin-film multilayers, where the strong bonds existing at the interface between the superconductor and the magnetic material should in principle enhance proximity effects and strengthen any electronic correlations. Here, we fabricate devices based on van der Waals (vdW) stacks of flakes of the Nb S 2 combined with flakes of C r 1/3 Nb S 2, which has a built-in magnetic inhomogeneity due to its helimagnetic spin texture at low temperatures. We find that the critical temperature of these vdW heterostructures is strongly dependent on the magnetic state of C r 1/3 Nb S 2, whose degree of magnetic inhomogeneity can be …

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Mar 2024 • Quantum Sensing, Imaging, and Precision Metrology II, PC129123Q, 2024

Advanced configurations for light-vapour interactions at the nanoscale

Uriel Levy


Mar 2024 • Ultrafast Phenomena and Nanophotonics XXVIII 12884, 90-91, 2024

Optical simulation of laser-induced tunnel ionization based on a curved waveguide

Arnon Ben Levy, Amir Hen, Merav Kahn, Yoad Aharon, Noa Mazurski, Uriel Levy, Gilad Marcus

In earlier work, we suggested using a curved waveguide as a quantum simulator to simulate the tunnel ionization process. Here we implemented for the first time such a simulator and tested our results against the Keldysh and bending loss ionization rates. We observed also straight rays which are reminiscent of above-threshold-ionization (ATI) electrons.

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Feb 2024 • ACS Photonics

Roadmap for optical metasurfaces

Arseniy I Kuznetsov, Mark L Brongersma, Jin Yao, Mu Ku Chen, Uriel Levy, Din Ping Tsai, Nikolay I Zheludev, Andrei Faraon, Amir Arbabi, Nanfang Yu, Debashis Chanda, Kenneth B Crozier, Alexander V Kildishev, Hao Wang, Joel KW Yang, Jason G Valentine, Patrice Genevet, Jonathan A Fan, Owen D Miller, Arka Majumdar, Johannes E Fröch, David Brady, Felix Heide, Ashok Veeraraghavan, Nader Engheta, Andrea Alù, Albert Polman, Harry A Atwater, Prachi Thureja, Ramon Paniagua-Dominguez, Son Tung Ha, Angela I Barreda, Jon A Schuller, Isabelle Staude, Gustavo Grinblat, Yuri Kivshar, Samuel Peana, Susanne F Yelin, Alexander Senichev, Vladimir M Shalaev, Soham Saha, Alexandra Boltasseva, Junsuk Rho, Dong Kyo Oh, Joohoon Kim, Junghyun Park, Robert Devlin, Ragip A Pala

Metasurfaces have recently risen to prominence in optical research, providing unique functionalities that can be used for imaging, beam forming, holography, polarimetry, and many more, while keeping device dimensions small. Despite the fact that a vast range of basic metasurface designs has already been thoroughly studied in the literature, the number of metasurface-related papers is still growing at a rapid pace, as metasurface research is now spreading to adjacent fields, including computational imaging, augmented and virtual reality, automotive, display, biosensing, nonlinear, quantum and topological optics, optical computing, and more. At the same time, the ability of metasurfaces to perform optical functions in much more compact optical systems has triggered strong and constantly growing interest from various industries that greatly benefit from the availability of miniaturized, highly functional, and efficient …

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Feb 2024 • Advanced Optical Materials

Silicon Rich Nitride Huygens Metasurfaces in the Visible Regime

Oren Goldberg, Rivka Gherabli, Jacob Engelberg, Jinan Nijem, Noa Mazurski, Uriel Levy

In recent years there has been a shift of interest in the Nanophotonics community moving from using metallic/plasmonic materials to using high‐index dielectric materials for the construction of metasurfaces. Although high‐index dielectrics hold many advantages over their plasmonic counterparts, the selection of materials that exhibit high‐index properties, have low loss, and are complemetary metal‐oxide‐semiconductor (CMOS) compatible that also operate in the visible regime is extremely challenging. In this work, a high‐index dielectric material using silicon rich nitride (SRN) is proposed and experimentally demonstrated as a platform for solving this problem. While SRN has been used before for diffractive lenses and structural colors, here its applicability for Huygens‐type metasurfaces is focused upon. Specifically, a Huygens metasurface that operates in the visible range around a wavelength of 575 nm is …

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Feb 2024 • Optics Express

High-Q and high finesse silicon microring resonator

Jinan Nijem, Alex Naiman, Roy Zektzer, Christian Frydendahl, Noa Mazurski, Uriel Levy

We demonstrate the design, fabrication, and experimental characterization of a single transverse mode adiabatic microring resonator (MRR) implemented using the silicon-on-insulator (SOI) platform using local oxidation of silicon (LOCOS) approach. Following its fabrication, the device was characterized experimentally and an ultrahigh intrinsic Q-factor of∼ 2 million with a free spectral range (FSR) of 2 nm was achieved, giving rise to a finesse of∼ 1100, the highest demonstrated so far in SOI platform at the telecom band. We have further studied our device to analyze the source of losses that occur in the MRR and to understand the limits of the achievable Q-factor. The surface roughness was quantified using AFM scans and the root mean square roughness was found to be∼ 0.32±0.03 nm. The nonlinear losses were further examined by coupling different optical power levels into the MRR. Indeed, we could …

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Feb 2024 • ACS Photonics

Roadmap for Optical Metasurfaces

Arseniy I Kuznetsov, Mark L Brongersma, Jin Yao, Mu Ku Chen, Uriel Levy, Din Ping Tsai, Nikolay I Zheludev, Andrei Faraon, Amir Arbabi, Nanfang Yu, Debashis Chanda, Kenneth B Crozier, Alexander V Kildishev, Hao Wang, Joel KW Yang, Jason G Valentine, Patrice Genevet, Jonathan A Fan, Owen D Miller, Arka Majumdar, Johannes E Fröch, David Brady, Felix Heide, Ashok Veeraraghavan, Nader Engheta, Andrea Alù, Albert Polman, Harry A Atwater, Prachi Thureja, Ramon Paniagua-Dominguez, Son Tung Ha, Angela I Barreda, Jon A Schuller, Isabelle Staude, Gustavo Grinblat, Yuri Kivshar, Samuel Peana, Susanne F Yelin, Alexander Senichev, Vladimir M Shalaev, Soham Saha, Alexandra Boltasseva, Junsuk Rho, Dong Kyo Oh, Joohoon Kim, Junghyun Park, Robert Devlin, Ragip A Pala

Metasurfaces have recently risen to prominence in optical research, providing unique functionalities that can be used for imaging, beam forming, holography, polarimetry, and many more, while keeping device dimensions small. Despite the fact that a vast range of basic metasurface designs has already been thoroughly studied in the literature, the number of metasurface-related papers is still growing at a rapid pace, as metasurface research is now spreading to adjacent fields, including computational imaging, augmented and virtual reality, automotive, display, biosensing, nonlinear, quantum and topological optics, optical computing, and more. At the same time, the ability of metasurfaces to perform optical functions in much more compact optical systems has triggered strong and constantly growing interest from various industries that greatly benefit from the availability of miniaturized, highly functional, and efficient …

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Feb 2024 • Optics Express

High-Q and high finesse silicon microring resonator

Jinan Nijem, Alex Naiman, Roy Zektzer, Christian Frydendahl, Noa Mazurski, Uriel Levy

We demonstrate the design, fabrication, and experimental characterization of a single transverse mode adiabatic microring resonator (MRR) implemented using the silicon-on- insulator (SOI) platform using local oxidation of silicon (LOCOS) approach. Following its fabrication, the device was characterized experimentally and an ultrahigh intrinsic Q-factor of ∼2 million with a free spectral range (FSR) of 2 nm was achieved, giving rise to a finesse of ∼1100, the highest demonstrated so far in SOI platform at the telecom band. We have further studied our device to analyze the source of losses that occur in the MRR and to understand the limits of the achievable Q-factor. The surface roughness was quantified using AFM scans and the root mean square roughness was found to be ∼ 0.32±0.03 nm. The nonlinear losses were further examined by coupling different optical power levels into the MRR. Indeed, we could …

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Feb 2024 • Journal of Colloid and Interface Science

A self-standing superhydrophobic material formed by the self-assembly of an individual amino acid

Tan Hu, Zhuo Zhang, Meital Reches

HypothesisThere is a growing interest in designing superhydrophobic materials for many applications including self-clean surfaces, separation systems, and antifouling solutions. Peptides and amino acids offer attractive building blocks for these materials since they are biocompatible and biodegradable and can self-assemble into complex ordered structures.Experiments and SimulationsWe designed a self-standing superhydrophobic material through the self-assembly of an individual functionalized aromatic amino acid, Cbz-Phe(4F). The self-assembly of Cbz-Phe(4F) was investigated by experimental and computational methods. Moreover, when drop-casted three times on a solid support, it formed a self-standing superhydrophobic material. The mechanical properties and chemical stability of this self-standing superhydrophobic material were demonstrated.FindingsThe designed Cbz-Phe(4F) self-assembled into …

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Feb 2024 • Chem

A multifunctional drug delivery system based on switchable peptide-stabilized emulsions

Daniel Boas, Alexander van Teijlingen, Zohar Shpilt, Deborah E Shalev, Edit Y Tshuva, Tell Tuttle, Meital Reches

Emulsions are commonly used for drug delivery, yet they are usually limited to exclusively delivering either lipophilic or hydrophilic compounds. This separation negates possible synergetic therapeutic roles between such compounds. Here, we introduce a design for a short peptide that can stabilize emulsions. Upon binding certain metal ions, the peptide acts as a molecular switch, changes conformation, and becomes amphiphilic. Spectroscopic methods, NMR, and molecular dynamics provide information on the mechanism of this complexation-triggered amphiphilicity. The stability of these unique emulsions is based on histidine-metal bonds, which break at low pH values, selectively releasing their contents at the extracellular pH of tumors. Paclitaxel-encapsulated emulsion demonstrates strong activity against HeLa cells with an IC50 of 70 nM, possibly enhanced by the simultaneous release of Zn2+ ions …

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Jan 2024 • iScience

Factors influencing initial bacterial adhesion to antifouling surfaces studied by single-cell force spectroscopy

Tal Duanis-Assaf, Meital Reches

Biofilm formation, a major concern for healthcare systems, is initiated when bacteria adhere to surfaces. Escherichia coli adhesion is mediated by appendages, including type-1 fimbriae and curli amyloid fibers. Antifouling surfaces prevent the adhesion of bacteria to combat biofilm formation. Here, we used single-cell force-spectroscopy to study the interaction between E. coli and glass or two antifouling surfaces: the tripeptide DOPA-Phe(4F)-Phe(4F)-OMe and poly(ethyleneglycol) polymer-brush. Our results indicate that both antifoulants significantly deter E. coli initial adhesion. By using two mutant strains expressing no type-1 fimbriae or curli amyloids, we studied the adhesion mechanism. Our results suggest that the bacteria adhere to different antifoulants via separate mechanisms. Finally, we show that some bacteria adhere much better than others, illustrating how the variability of bacterial cultures affects biofilm …

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Jan 2024 • Biomacromolecules

Self-Assembly of a Dipeptide with a Reduced Amount of Copper into Antifungal and Antibacterial Particles

Michaela Kaganovich, Mohammad Taha, Uri Zig, Edit Y Tshuva, Deborah E Shalev, Abraham Gamliel, Meital Reches

With the growing concern over the environmental impact and health risks associated with conventional pesticides, there is a great need for developing safer and more sustainable alternatives. This study demonstrates the self-assembly of antimicrobial and antifungal spherical particles by a dipeptide utilizing a reduced amount of copper salt compared to the commonly employed formulation. The particles can be sprayed on a surface and form an antimicrobial coating. The effectiveness of the coating against the bacteria Pectobacterium brasiliense, a common pathogen affecting potato crops, was demonstrated, as the coating reduced the bacterial load by 7.3 log. Moreover, a comprehensive field trial was conducted, where the formulation was applied to potato seeds. Remarkably, it exhibited good efficacy against three prevalent potato pathogens (P. brasiliense, Pythium spp., and Spongospora subterranea) while …

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Jan 2024 • Advanced Optical Materials

Tunable Second Harmonic Generation with Large Enhancement in A Nonlocal All‐Dielectric Metasurface Over A Broad Spectral Range

Hui Jiang, Kaili Sun, Yuechen Jia, Yangjian Cai, Uriel Levy, Zhanghua Han

Recently, all‐dielectric metasurfaces are profoundly exploited to enhance light‐matter interactions, resulting from the high quality‐factor (Q‐factor) optical resonances that based on novel concepts such as the bound states in the continuum (BIC). Unfortunately, BIC operates at a fixed resonance wavelength and a fixed wavevector for a specific structure. Here, the experimental demonstration of a dielectric nonlocal metasurface capable of robustly maintaining high‐Q resonances is reported, over a broad spectral range, where the specific wavelength is selected by controlling the incident angle. This is enabled by steering infinite‐Q guided modes (GMs) in subwavelength lattices into quasi‐GMs (QGMs), which are accessible by external radiations while retaining the same dispersion as the GMs. Such invaluable characteristics are achieved by harnessing the period‐doubling perturbation, implemented in a nonlocal …

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Jan 2024 • Nano Letters

Exploiting Zone-Folding Induced Quasi-Bound Modes to Achieve Highly Coherent Thermal Emissions

Kaili Sun, Uriel Levy, Zhanghua Han

Thermal emissions with high coherence, although not as high as those of lasers, still play a crucial role in many practical applications. In this work, by exploiting the geometric perturbation-induced optical lattice tripling and the associated Brillion zone folding effect, we propose and investigate thermal emissions in the mid-infrared with simultaneous high temporal and spatial coherence. In contrast with the case of period-doubling perturbation in our previous work, the steeper part of the guided mode dispersion band will be folded to the high-symmetry Γ point in the ternary grating. In this case, a specific emission wavelength corresponds to only a very small range of wavevectors. Consequently, apart from the high temporal coherence characterized by an experimental bandwidth around 30 nm, the achieved thermal emissions also feature ultrahigh spatial coherence. Calculations show that at the thermal emission …

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Jan 2024 • Advanced Optical Materials

Tunable Second Harmonic Generation with Large Enhancement in A Nonlocal All‐Dielectric Metasurface Over A Broad Spectral Range

Hui Jiang, Kaili Sun, Yuechen Jia, Yangjian Cai, Uriel Levy, Zhanghua Han

Recently, all‐dielectric metasurfaces are profoundly exploited to enhance light‐matter interactions, resulting from the high quality‐factor (Q‐factor) optical resonances that based on novel concepts such as the bound states in the continuum (BIC). Unfortunately, BIC operates at a fixed resonance wavelength and a fixed wavevector for a specific structure. Here, the experimental demonstration of a dielectric nonlocal metasurface capable of robustly maintaining high‐Q resonances is reported, over a broad spectral range, where the specific wavelength is selected by controlling the incident angle. This is enabled by steering infinite‐Q guided modes (GMs) in subwavelength lattices into quasi‐GMs (QGMs), which are accessible by external radiations while retaining the same dispersion as the GMs. Such invaluable characteristics are achieved by harnessing the period‐doubling perturbation, implemented in a nonlocal …

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2024 • bioRxiv

A study on tomato brown rugose fruit virus longevity in soil and virion susceptibility to various pH treatments contributes to optimization of a soil disinfection protocol

Ori Molad, Elisheva Smith, Neta Luria, Elena Bakelman, Oded Lachman, Meital Reches, Aviv Dombrovsky

Background and aims Tobamoviruses are highly stable soil-borne pathogens posing a challenge to a monoculture practice. Biochemical and physical properties of tobamovirus virions were studied by analyses of tobacco mosaic virus (TMV). Little is known about tomato brown rugose fruit tobamovirus (ToBRFV) regarding longevity in soil and virion stability. Our aims were to determine ToBRFV longevity in naturally-contaminated soil and study virion stability in a range of acidic and alkaline conditions to promote new strategies for soil remediation. Methods ToBRFV longevity in naturally-contaminated soil was tested by collecting an earth pile after a growth-cycle of ToBRFV-infected tomato plants. The soil was sampled at different time points and root-truncated tomato seedlings were planted. Virion stability at a range of pH values was determined by testing virus infectivity on Nicotiana glutinosa; by amplifying large genome segments using RT-PCR; and by transmission electron microscopy (TEM) visualization. Results ToBRFV-infectivity in naturally-contaminated soil was profoundly reduced by day 184 of pile-age and was abolished between 205-385 days of pile-age. Virion stability and genome integrity were preserved over the pH range of 2-10. At pH 1, ToBRFV-infectivity and efficiency of large genome segment amplifications were reduced. At pH values above 10, modified particle morphologies were visualized by TEM, and virus infectivity was abolished. Treatment of ToBRFV-contaminated soil with an alkaline chlorinated-trisodium phosphate solution profoundly reduced soil-mediated virus infection of root-truncated tomato seedlings …

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