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Jul 2023 • Fuel

Design of three-dimensional hexagonal petal-like nickel-copper cobaltite//luffa sponge-derived activated carbon electrode materials for high-performance solid-state supercapattery

Sengodan Prabhu, Moorthy Maruthapandi, Arulappan Durairaj, S Arun Kumar, John HT Luong, Rajendran Ramesh, Aharon Gedanken

Three-dimensional porous nanostructured materials are considered superior materials for energy storage applications due to their high storage capability. A nickel copper-cobalt oxide (NCC) composite with a uniform 3-D porous nanostructure (positive electrode materials) and luffa sponge-derived activated carbon (LPAC) with honeycomb-like structure (negative electrode materials) were synthesized by a simple hydrothermal and chemical method. A sample of the nickel-copper cobalt oxide-5 (NCC-5) nanocomposite reached a high specific capacitance of 1048 F/g at the current density of 0.5 A/g. The NCC-5 nanocomposite sample shows a retention capacity of 93 % after 10,000 charge and discharge cycles with 95 % of Coulombic efficiency (CE). The LPAC illustrates a remarkable specific capacitance of 909 F/g at 1 A/g of current density, compared to the best literature value of 400 F/g. The full-cell NCC-5//LPAC …

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Jun 2023 • Journal of Power Sources

Zn-enriched cathode layer interface via atomic surface reduction of LiNi0. 5Mn1. 5O4: Computational and experimental insights

Shubham Garg, Sarah Taragin, Arka Saha, Olga Brontvein, Kevin Leung, Malachi Noked

Despite having the ability to deliver 650 W h kg−1 in addition to the impressive rate capability, superior thermal stability, and facilitated electronic and ionic lithium conduction, LiNi0.5Mn1.5O4 (LNMO) is far from commercial applications. LNMO suffers from irreversible electrolytic degradation on its surface under high voltage operations leading to capacity fading and poor battery life. Therefore, this work aims to improve the stability and electrochemical behavior of LNMO by creating a Zn-enriched cathode layer interface via eccentric and facile diethyl zinc-assisted atomic surface reduction (Zn-ASR). In-depth surface characterization tools and computational calculations demonstrates a conformal 7-8 nm thin Zn-O and C-O enriched layer encapsulating the cathode particles resulting from Zn-ASR. The intensive comparative electrochemical and spectroscopic analysis, indicates superior electrochemical performance of …

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Jun 2023 • Bulletin of the American Physical Society

Understanding Multichannel nature of Efimov physics with ultracold 7Li atoms

Jose P D'Incao, Yaakov Yudkin, Paul Julienne, Lev Khaykovich

We present our current understanding of various aspects of Efimov physics originating from the complex multichannel hyperfine structure which further help us to understand puzzling 7Li experimental observations. Our results indicates that spin-exchange for 7Li atoms play an important role in the determination of Efimov resonances along with the narrow character of its Feshbach resonances. We show that the structure of three-body potentials is strongly dependent on the resonance width giving further insights to other atomic species.

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Jun 2023 • Materials Today Chemistry

Thin coating of silica/polystyrene core-shell nano/microparticles with hierarchical morphology onto polymeric films for fabrication of superhydrophobic surfaces

S Hayne, S Margel

A novel coating process applied directly onto polymeric films offers a long-term alternative to short-term surface treatment of low surface energy polymers. In this paper, we report (i) an improved synthesis of a coating of raspberry-like particles directly onto polymeric surfaces and (ii) a novel method to obtain films with out-of-the ordinary superhydrophobic and self-cleaning properties. Inspired by the ‘lotus effect’ observed in nature, superhydrophobic surfaces were fabricated by combining dual-scale hierarchical coatings with low surface energy fluoroalkanes. Raspberry-like core-shell microparticles (MPs) composed of polystyrene (PS) core coated with silica (SiO2) shell (SiO2/PS) were synthesized by in situ dispersion polymerization of styrene directly on the surface of corona-treated polypropylene films. The PS MPs covered surface was then coated with SiO2 nano/microparticles (N/MPs) forming a hierarchical …

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May 2023 • arXiv preprint arXiv:2205.08563

Majorana-Weyl cones in ferroelectric superconductors

Hennadii Yerzhakov, Roni Ilan, Efrat Shimshoni, Jonathan Ruhman

Topological superconductors are predicted to exhibit outstanding phenomena, including non-abelian anyon excitations, heat-carrying edge states, and topological nodes in the Bogoliubov spectra. Nonetheless, and despite major experimental efforts, we are still lacking unambiguous signatures of such exotic phenomena. In this context, the recent discovery of coexisting superconductivity and ferroelectricity in lightly doped and ultra clean SrTiO opens new opportunities. Indeed, a promising route to engineer topological superconductivity is the combination of strong spin-orbit coupling and inversion-symmetry breaking. Here we study a three-dimensional parabolic band minimum with Rashba spin-orbit coupling, whose axis is aligned by the direction of a ferroelectric moment. We show that all of the aforementioned phenomena naturally emerge in this model when a magnetic field is applied. Above a critical Zeeman field, Majorana-Weyl cones emerge regardless of the electronic density. These cones manifest themselves as Majorana arcs states appearing on surfaces and tetragonal domain walls. Rotating the magnetic field with respect to the direction of the ferroelectric moment tilts the Majorana-Weyl cones, eventually driving them into the type-II state with Bogoliubov Fermi surfaces. We then consider the consequences of the orbital magnetic field. First, the single vortex is found to be surrounded by a topological halo, and is characterized by two Majorana zero modes: One localized in the vortex core and the other on the boundary of the topological halo. For a finite density of vortices forming close enough to the upper critical field, these halos …

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May 2023 • Journal of Functional Biomaterials

Engineered Cross-Linked Silane with Urea Polymer Thin Durable Coatings onto Polymeric Films for Controlled Antiviral Release of Activated Chlorine and Essential Oils

Elisheva Sasson, Omer Agazani, Eyal Malka, Meital Reches, Shlomo Margel

In March 2020, the World Health Organization announced a pandemic attributed to SARS-CoV-2, a novel beta-coronavirus, which spread widely from China. As a result, the need for antiviral surfaces has increased significantly. Here, the preparation and characterization of new antiviral coatings on polycarbonate (PC) for controlled release of activated chlorine (Cl+) and thymol separately and combined are described. Thin coatings were prepared by polymerization of 1-[3-(trimethoxysilyl)propyl] urea (TMSPU) in ethanol/water basic solution by modified Stöber polymerization, followed by spreading the formed dispersion onto surface-oxidized PC film using a Mayer rod with appropriate thickness. Activated Cl-releasing coating was prepared by chlorination of the PC/SiO2-urea film with NaOCl through the urea amide groups to form a Cl-amine derivatized coating. Thymol releasing coating was prepared by linking thymol to TMSPU or its polymer via hydrogen bonds between thymol hydroxyl and urea amide groups. The activity towards T4 bacteriophage and canine coronavirus (CCV) was measured. PC/SiO2-urea-thymol enhanced bacteriophage persistence, while PC/SiO2-urea-Cl reduced its amount by 84%. Temperature-dependent release is presented. Surprisingly, the combination of thymol and chlorine had an improved antiviral activity, reducing the amount of both viruses by four orders of magnitude, indicating synergistic activity. For CCV, coating with only thymol was inactive, while SiO2-urea-Cl reduced it below a detectable level.

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May 2023 • ACS Applied Materials & Interfaces

Topotactic, Vapor-Phase, In Situ Monitored Formation of Ultrathin, Phase-Pure 2D-on-3D Halide Perovskite Surfaces

Sujit Kumar, Vinayaka H Damle, Tatyana Bendikov, Anat Itzhak, Michael Elbaum, Katya Rechav, Lothar Houben, Yaakov Tischler, David Cahen

Two-dimensional (2D) halide perovskites, HaPs, can provide chemical stability to three-dimensional (3D) HaP surfaces, protecting them from exposure to ambient species and from reacting with contacting layers. Both actions occur with 2D HaPs, with the general stoichiometry R2PbI4 (R: long or bulky organic amine) covering the 3D ones. Adding such covering films can also boost power conversion efficiencies of photovoltaic cells by passivating surface/interface trap states. For maximum benefit, we need conformal ultrathin and phase-pure (n = 1) 2D layers to enable efficient tunneling of photogenerated charge carriers through the 2D film barrier. Conformal coverage of ultrathin (<10 nm) R2PbI4 layers on 3D perovskites is challenging with spin coating; even more so is its upscaling for larger-area devices. We report on vapor-phase cation exchange of the 3D surface with the R2PbI4 molecules and real-time in situ …

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May 2023 • ACS Energy Letters

A-Site Cation Dependence of Self-Healing in Polycrystalline APbI3 Perovskite Films

Pallavi Singh, Yahel Soffer, Davide Raffaele Ceratti, Michael Elbaum, Dan Oron, Gary Hodes, David Cahen

In terms of sustainable use, halide perovskite (HaP) semiconductors have a strong advantage over most other classes of materials for (opto)electronics, as they can self-heal (SH) from photodamage. While there is considerable literature on SH in devices, where it may not be clear exactly where damage and SH occur, there is much less on the HaP material itself. Here we perform “fluorescence recovery after photobleaching” (FRAP) measurements to study SH on polycrystalline thin films for which encapsulation is critical to achieving complete and fast self-healing. We compare SH in three photoactive APbI3 perovskite films by varying the A-site cation ranging from (relatively) small inorganic Cs through medium-sized MA to large FA (the last two are organic cations). While the A cation is often considered electronically relatively inactive, it significantly affects both SH kinetics and the threshold for photodamage. The …

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May 2023 • Colloids and Surfaces B: Biointerfaces

A green formulation for superhydrophobic coatings based on Pickering emulsion templating for anti-biofilm applications

Raz Cohen, Karthik Ananth Mani, Madina Primatova, Gila Jacobi, Einat Zelinger, Eduard Belausov, Elazar Fallik, Ehud Banin, Guy Mechrez

This study reports significant steps toward developing anti-biofilm surfaces based on superhydrophobic properties that meet the complex demands of today's food and medical regulations. It presents inverse Pickering emulsions of water in dimethyl carbonate (DMC) stabilized by hydrophobic silica (R202) as a possible food-grade coating formulation and describes its significant passive anti-biofilm properties. The final coatings are formed by applying the emulsions on the target surface, followed by evaporation to form a rough layer. Analysis shows that the final coatings exhibited a Contact Angle (CA) of up to 155° and a Roll-off Angle (RA) lower than 1° on the polypropylene (PP) surface, along with a relatively high light transition. Dissolving polycaprolactone (PCL) into the continuous phase enhanced the average CA and coating uniformity but hindered the anti-biofilm activity and light transmission. Scanning …

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May 2023 • Journal of Biomedical Optics

Imaging the rotational mobility of carbon dot-gold nanoparticle conjugates using frequency domain wide-field time-resolved fluorescence anisotropy

Gilad Yahav, Shweta Pawar, Yitzchak Weber, Bar Atuar, Hamootal Duadi, Dror Fixler

SignificanceWide-field measurements of time-resolved fluorescence anisotropy (TR-FA) provide pixel-by-pixel information about the rotational mobility of fluorophores, reflecting changes in the local microviscosity and other factors influencing the fluorophore’s diffusional motion. These features offer promising potential in many research fields, including cellular imaging and biochemical sensing, as demonstrated by previous works. Nevertheless, θ imaging is still rarely investigated in general and in carbon dots (CDs) in particular.AimTo extend existing frequency domain (FD) fluorescence lifetime (FLT) imaging microscopy (FLIM) to FD TR-FA imaging (TR-FAIM), which produces visual maps of the FLT and θ, together with the steady-state images of fluorescence intensity (FI) and FA (r).

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May 2023 • Physical Review A

High-spectral-resolution absorption measurements with free-electron lasers using ghost spectroscopy

Yishai Klein, Alok K Tripathi, Edward Strizhevsky, Flavio Capotondi, Dario De Angelis, Luca Giannessi, Matteo Pancaldi, Emanuele Pedersoli, Kevin C Prince, Or Sefi, Young Yong Kim, Ivan A Vartanyants, Sharon Shwartz

We demonstrate a simple and robust high-resolution ghost spectroscopy approach for x-ray and extreme ultraviolet transient absorption spectroscopy at free-electron laser sources. To retrieve the sample response, our approach requires only an online spectrometer before the sample and a downstream bucket detector. We validate the method by measuring the absorption spectrum of silicon, silicon carbide, and silicon nitride membranes in the vicinity of the silicon L 2, 3 edge and by comparing the results with standard techniques for absorption measurements. Moreover, we show that ghost spectroscopy allows the high-resolution reconstruction of the sample spectral response to optical pumps using a coarse energy scan with self-amplified spontaneous emission radiation.

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May 2023 • arXiv preprint arXiv:2305.04888

Phase diagram of the quantum Hall state in bilayer graphene

Udit Khanna, Ke Huang, Ganpathy Murthy, HA Fertig, Kenji Watanabe, Takashi Taniguchi, Jun Zhu, Efrat Shimshoni

Bilayer graphene exhibits a rich phase diagram in the quantum Hall regime, arising from a multitude of internal degrees of freedom, including spin, valley, and orbital indices. The variety of fractional quantum Hall states between filling factors suggests, among other things, a quantum phase transition between valley-unpolarized and polarized states at a perpendicular electric field . We find the behavior of with changes markedly as is reduced. At , may even vanish when is sufficiently small. We present a theoretical model for lattice-scale interactions which explains these observations; surprisingly, both repulsive and attractive components in the interactions are required. Within this model we analyze the nature of the state as a function of the magnetic and electric fields, and predict that valley-coherence may emerge for in the high regime. This suggests the system supports Kekule bond-ordering, which could in principle be verified via STM measurements.

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May 2023 • Journal of Applied Physics

Parallel array of planar Hall effect sensors for high resolution magnetometry

Hariharan Nhalil, Moty Schultz, Shai Amrusi, Asaf Grosz, Lior Klein

We introduce a planar Hall effect magnetometer in the form of a parallel array of permalloy-based elliptical sensors. The number of ellipses in the array and other fabrication parameters are optimized with the support of numerical simulations. We obtain equivalent magnetic noise (EMN) of 16 pT/ffiffiffiffiffiffi Hz p at 100 Hz, 25 pT/ffiffiffiffiffiffi Hz p at 10 Hz, 98 pT/ffiffiffiffiffiffi Hz p at 1 Hz, and 470 pT/ffiffiffiffiffiffi Hz p at 0.1 Hz. The exceptional EMN without the use of magnetic flux concentrators highlights the advantages of the design. The presented magnetometer, characterized by its simplicity, affordability, and ability to operate at room temperature, is anticipated to be useful for applications requiring pT resolution.

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May 2023 • arXiv preprint arXiv:2305.12468

High-resolution computed tomography with scattered x-ray radiation and a single pixel detector

A Ben Yehuda, O Sefi, Y Klein, RH Shukrun, H Schwartz, E Cohen, S Shwartz

X-ray imaging is a prevalent technique for non-invasively visualizing the interior of the human body and opaque instruments. In most commercial x-ray modalities, an image is formed by measuring the x-rays that pass through the object of interest. However, despite the potential of scattered radiation to provide additional information about the object, it is often disregarded due to its inherent tendency to cause blurring. Consequently, conventional imaging modalities do not measure or utilize these valuable data. In contrast, we propose and experimentally demonstrate a high-resolution technique for x-ray computed tomography (CT) that measures scattered radiation by exploiting computational ghost imaging (CGI). We show that our method can provide sub-200 {\mu}m resolution, exceeding the capabilities of most existing x-ray imaging modalities. Our research reveals a promising technique for incorporating scattered radiation data in CT scans to improve image resolution and minimize radiation exposure for patients. The findings of our study suggest that our technique could represent a significant advancement in the fields of medical and industrial imaging, with the potential to enhance the accuracy and safety of diagnostic imaging procedures.

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May 2023 • arXiv preprint arXiv:2205.01974

Restart expedites quantum walk hitting times

Ruoyu Yin, Eli Barkai

Classical first-passage times under restart are used in a wide variety of models, yet the quantum version of the problem still misses key concepts. We study the quantum first detected passage time under restart protocol using a monitored quantum walk. The restart strategy eliminates the problem of dark states, i.e. cases where the particle is not detected at all, while maintaining the ballistic propagation which is important for fast search. We find profound effects of quantum oscillations on the restart problem, namely a type of instability of the mean detection time, and optimal restart times that form staircases, with sudden drops as the rate of sampling is modified. In the absence of restart and in the Zeno limit, the detection of the walker is not possible and we examine how restart overcomes this well-known problem, showing that the optimal restart time becomes insensitive to the sampling period.

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May 2023 • IEEE Transactions on Applied Superconductivity

Energy Storing and Fault Current Limiting in a Unified Superconducting Magnetic Device

Y Nikulshin, A Kafri, Y Yeshurun, S Wolfus

This work describes a novel concept for unifying Superconducting Magnetic Energy Storage (SMES) and an inductive-type Fault Current Limiter (FCL). A single superconducting coil is used both as an energy source for the operation of the SMES and as the field source for saturating the magnetic cores in the FCL. A possible geometry model for the implementation of this concept is suggested and a test case in an 11 kV, 10 MVA network is described for a fully, and 50% charged SMES states. Results show that the Saturated Cores FCL exhibits low insertion impedance and high limiting ratio in both scenarios. The unified SMES-FCL device saves major resources by making the superconducting coil a dual-purpose source, thus opening the door for an easier and efficient implementation of SMES and FCL technologies.

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May 2023 • PNAS Nexus

Experimentally probing anomalous time evolution of a single photon

Ryo Okamoto, Eliahu Cohen

In quantum mechanics, a quantum system is irreversibly collapsed by a projective measurement. Hence, delicately probing the time evolution of a quantum system holds the key to understanding curious phenomena. Here we experimentally explore an anomalous time evolution, where, illustratively, a particle disappears from a box and emerges in a different box, with a certain moment in which it can be found in neither of them. In this experiment, we directly probe this curious time evolution of a single photon by measuring up to triple-operator sequential weak values using a novel probeless scheme. The naive interpretation provided by single-operator weak values seems to imply the “disappearance” and “re-appearance” of a photon as theoretically predicted. However, double- and triple-operator sequential weak values, representing temporal correlations between the aforementioned values, show that spatial …

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May 2023 • Nature

Author Correction: Magnetic memory and spontaneous vortices in a van der Waals superconductor

Eylon Persky, Anders V Bjørlig, Irena Feldman, Avior Almoalem, Ehud Altman, Erez Berg, Itamar Kimchi, Jonathan Ruhman, Amit Kanigel, Beena Kalisky

In the version of this article initially published, the images presented in Extended Data Figure 2 were inadvertent duplicates of Figure 2c–e and are now updated in the HTML and PDF versions of the article.

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May 2023 • The Journal of Immunology

Flairr-seq: A method for single-molecule resolution of near full-length antibody H chain repertoires

Easton E Ford, David Tieri, Oscar L Rodriguez, Nancy J Francoeur, Juan Soto, Justin T Kos, Ayelet Peres, William S Gibson, Catherine A Silver, Gintaras Deikus, Elizabeth Hudson, Cassandra R Woolley, Noam Beckmann, Alexander Charney, Thomas C Mitchell, Gur Yaari, Robert P Sebra, Corey T Watson, Melissa L Smith

Current Adaptive Immune Receptor Repertoire sequencing (AIRR-seq) using short-read sequencing strategies resolve expressed Ab transcripts with limited resolution of the C region. In this article, we present the near-full-length AIRR-seq (FLAIRR-seq) method that uses targeted amplification by 5′ RACE, combined with single-molecule, real-time sequencing to generate highly accurate (99.99%) human Ab H chain transcripts. FLAIRR-seq was benchmarked by comparing H chain V (IGHV), D (IGHD), and J (IGHJ) gene usage, complementarity-determining region 3 length, and somatic hypermutation to matched datasets generated with standard 5′ RACE AIRR-seq using short-read sequencing and full-length isoform sequencing. Together, these data demonstrate robust FLAIRR-seq performance using RNA samples derived from PBMCs, purified B cells, and whole blood, which recapitulated results generated by …

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May 2023 • arXiv preprint arXiv:2305.05258

FEL stochastic spectroscopy revealing silicon bond softening dynamics

Dario De Angelis, Emiliano Principi, Filippo Bencivenga, Daniele Fausti, Laura Foglia, Yishay Klein, Michele Manfredda, Riccardo Mincigrucci, Angela Montanaro, Emanuele Pedersoli, Jacopo Stefano Pelli Cresi, Giovanni Perosa, Kevin C Prince, Elia Razzoli, Sharon Shwartz, Alberto Simoncig, Simone Spampinati, Cristian Svetina, Jakub Szlachetko, Alok Tripathi, Ivan A Vartanyants, Marco Zangrando, Flavio Capotondi

Time-resolved X-ray Emission/Absorption Spectroscopy (Tr-XES/XAS) is an informative experimental tool sensitive to electronic dynamics in materials, widely exploited in diverse research fields. Typically, Tr-XES/XAS requires X-ray pulses with both a narrow bandwidth and sub-picosecond pulse duration, a combination that in principle finds its optimum with Fourier transform-limited pulses. In this work, we explore an alternative xperimental approach, capable of simultaneously retrieving information about unoccupied (XAS) and occupied (XES) states from the stochastic fluctuations of broadband extreme ultraviolet pulses of a free-electron laser. We used this method, in combination with singular value decomposition and Tikhonov regularization procedures, to determine the XAS/XES response from a crystalline silicon sample at the L2,3-edge, with an energy resolution of a few tens of meV. Finally, we combined this spectroscopic method with a pump-probe approach to measure structural and electronic dynamics of a silicon membrane. Tr-XAS/XES data obtained after photoexcitation with an optical laser pulse at 390 nm allowed us to observe perturbations of the band structure, which are compatible with the formation of the predicted precursor state of a non-thermal solid-liquid phase transition associated with a bond softening phenomenon.

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May 2023 • Scientific Reports

Publisher Correction: Optical reciprocity induced wavefront shaping for axial and lateral shifting of focus through a scattering medium

Abhijit Sanjeev, Vismay Trivedi, Zeev Zalevsky

Publisher Correction: Optical reciprocity induced wavefront shaping for axial and lateral shifting of focus through a scattering Page 1 1 Vol.:(0123456789) Scientific Reports | (2023) 13:7525 | Publisher Correction: Optical reciprocity induced wavefront shaping for axial and lateral shifting of focus through a scattering medium Abhijit Sanjeev , Vismay Trivedi & Zeev Zalevsky Correction to: Scientific Reports https:// doi. org/ 10. 1038/ s41598- 022- 10378-7, published online 16 April 2022 The original version of this Article contained an error in Eq. 1, where the equation contained wrong placements of bracket, a misplaced matrix, and devoid of the power M. now reads: ∗ 0 0 ⋮ 0 ⋮ 0 0 0 ⋮ 0 ⋮ 0 (1) (Free Space Propagation Matrix) (Phase Scattering Matrix) OPEN Page 2 2 Vol:.(1234567890) Scientific Reports | (2023) 13:7525 |…

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