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Very thin conductive fibers, whose diameter is much smaller than the wavelength, strongly absorb and scatter electromagnetic radiation. The efficiency factors of absorption, scattering and radiation pressure of metal fibers with a diameter of several micrometers in the centimeter wavelength range reach several thousand. The absorption of electromagnetic radiation in two-layer fibers has been studied. In fibers with a metal core and a lossless dielectric cladding, the absorption is the same as in solid metal fibers. In lossy cladding fibers, strong absorption occurs when the fiber diameter is several nanometers. Fibers with a dielectric core and a metal cladding strongly absorb radiation when the thickness of the cladding is comparable to the thickness of the skin layer.

In this study, we investigate the energy loss of highly charged ions interacting with various tungsten surfaces. The analysis primarily focuses on elucidating the impact of electron density distributions on energy loss of ions. Furthermore, we explore the correlation between surface azimuthal angles and energy loss under both uniform and inhomogeneous electron density distributions. Utilizing the classical over-the-barrier model (COBM), simulations involving trajectory calculations, energy loss, charge-exchange processes, and surface electron distributions, etc., were performed. Remarkably, the significant influence of axial channeling of surfaces on ion energy loss is observed. For the comparison of ion energy loss under uniform and inhomogeneous electron density distributions, the results reveal a more pronounced effect of electron density inhomogeneity on ion energy loss at higher energy-loss values. Additionally, the calculated energy-loss spectra of Ar16+ ions grazing on graphite surfaces show reasonable agreement with experimental data. These findings are crucial for understanding the surface structure of crystals.

This work provides the first combined analysis of low-energy pΛ scattering, considering both cross section and correlation data. The obtained results establish the most stringent constraints to date on the two-body pΛ interaction, pointing to a weaker attraction than so far accepted. The best set of scattering lengths for the spin singlet and triplet are found to range from f0,f1=(2.1,1.56) to (3.34,1.18) fm. With a chiral NY potential fine-tuned to those scattering parameters, the in-medium properties of the Λ are explored and a potential depth of UΛ=−36.3±1.3(stat)−6.2+2.5(syst) MeV is found at nuclear matter saturation density.

Bethe’s theory predicts that scattering by a small hole on a thin perfect electric conductor (PEC) is presented as radiation by an in-plane magnetic dipole of the incident magnetic field direction. Even in the near-infrared range where metals are no more PEC, the magnetic dipole radiation of Bethe holes has been demonstrated. However, such Bethe holes’ nature has not been addressed yet in the ultraviolet (UV) range where conductivity of metals becomes severely deteriorated. Meanwhile, UV plasmonics has been elevating its importance in spectroscopy and photochemistry, recognizing silicon (Si) as an alternative plasmonic metal featuring the interband transition in the UV range. In this work, we expanded the Bethe’s theory’s prediction to the UV range by investigating Si Bethe holes theoretically and experimentally in terms of the scattering pattern and polarization. Simulation results showed that the scattered field distribution resembles that of an in-plane magnetic dipole, and the dipole direction at oblique incidence is roughly given as the incident magnetic field direction with a deviation angle which can be predicted from the Fresnel equations. Simulation with various diameters showed that the magnetic dipole nature maintains with a diameter less than the quarter-wavelength and multipoles becomes noticeable for diameters larger than the half-wavelength. We performed scattering polarization measurement at 69-degree incidence, which confirms the theoretical analysis. The features of Si Bethe holes demonstrated here will be useful for designing UV plasmonic metasurfaces.

The Bessel beams scattering of the fog particles were calculated by using the plane beams angle spectrum expansion method, and the effects of the topological charge and the half-conic angle of the Bessel beam on the differential scattering cross-section were analyzed by numerical calculation. Based on the scattering results of a single fog particle by a Bessel beam, by Monte Carlo method, the propagation characteristics of the Bessel beam in fogs with different visibility are simulated, and the effects of the wavelength, topological charge and semi-conic angle of the Bessel beam on transmissivity and reflectivity are analyzed. The studies show the self-healing ability of the Bessel beams, and the propagation distance of the Bessel beam is longer than that of the plane beams in fogs.

Abstract Water‐in‐oil (W/O) emulsions have attracted heightened attention because of the ever‐increasing interest in using non‐calorific water to replace calorie‐dense fat in food. However, designing clean‐label and ultra‐stable W/O emulsions is a longstanding challenge in colloid science. Herein, a novel, facile approach is introduced to designing cocoa butter (CB)‐based crystals to stabilize Pickering W/O emulsions. Results using a combination of small‐ and wide‐angle X‐ray scattering and microscopy across length scales reveal that the fat crystals formed in an oleogel of CB with vegetable oil offer high stability to water droplets (up to 60% (v/v)) against coalescence and phase inversion, over storage for 7 months. Such extraordinary stability is attributed to the nanoplatelet‐like CB crystals of βV polymorph located at the water–oil interface and to the inter‐droplet fat crystal network formation, interlocking the water droplets. The increment in water volume fraction endows gel‐like properties with the water droplets acting as “active fillers.” These newly designed Pickering W/O emulsions stabilized solely by fat crystals with unusual rigidity offer great promise for fabricating advanced functional materials in food, pharmaceutics, and cosmetic applications, where long‐term stabilization of water droplets using sustainable particles is a necessity.

Scattering phase shifts and annihilation rates for low-energy positrons interacting with noble gas atoms are calculated ab initio using many-body theory implemented in the Gaussian-orbital code EXCITON+. Specifically, we construct the positron–atom correlation potential (self-energy) as the sum of three classes of infinite series describing the screened polarization, virtual positronium formation, and positron-hole repulsion found via the solution of Bethe–Salpeter equations for the two-particle propagators. The normalization of the continuum states is determined using the shifted pseudostates method [A. R. Swann and G. F. Gribakin, Phys. Rev. A 101, 022702 (2020)]. Comparison with the previous sophisticated B-spline many-body approach, which is restricted to atoms [J. Ludlow, D. G. Green, and G. F. Gribakin, Phys. Rev. A 90, 032712 (2014)], validates the EXCITON+ code, which can be used for multicentered targets including molecules, clusters, and condensed matter. Moreover, the relative effects of higher-order diagrams are quantified. It is found that the screening of the electron–positron Coulomb interaction represented by the infinite ring-diagram series (random-phase approximation) is compensated effectively by the additional electron-hole attraction corrections to it (the Bethe–Salpeter equation approximation) and that the use of the screened Coulomb interaction (screened at BSE level) in place of the bare Coulomb interaction in the virtual positronium and positron-hole ladder diagrams has negligible effect on both the phase shifts and Zeff. Our scattering length for Ne and Kr is in improved agreement with the convergent close-coupling result, and for Ar, the scattering length is in better agreement with the experiment compared with the previous B-spline many-body approach.

We have studied reflection spectra of dye-doped and undoped polymers deposited onto Ag and Au substrates and found anomalous dips in the UV spectral range. On top of Ag substrates, the λ ∼ 375 nm dips were observed in undoped PMMA, PVP, and PS polymers as well as PMMA doped with Rh590 and HITC laser dyes. In silver-based samples, the spectral positions of the observed reflection dips were close to singularities in the refractive indexes of surface plasmon polaritons (SPPs) propagating at the interface between Ag and polymer. The latter singularities can tentatively explain the λ ∼ 375 nm reflection dips, if the scattering of Ag and polymeric films is large enough to launch SPP without any prism or grating. The dips observed in reflection of Rh590:PMMA and HITC:PMMA on top of Au, were more pronounced than those on Ag, broader, shifted to shorter wavelengths, and their spectral positions had large standard deviations. Furthermore, no anomalous dips in gold-based samples were observed in the reflection spectra of undoped PMMA, PVP, and PS polymers, and a modest singularity in the SPP refractive index, predicted theoretically at λ ∼ 500 nm, cannot explain the dips in the UV reflection spectra observed experimentally. It appears likely that the origin of the reflection dips on top of Au substrates is different from that on top of Ag substrates.

In severe low-visibility environments full of smoke, because of the performance degeneration of the near-infrared (NIR) collimation system of quantum drones communication networks, the improved dual-threshold method based on trend line analysis for long-wave infrared (LWIR) quantum cascade lasers (QCLs) is proposed, to achieve target acquisition. The simulation results show that smoke-scattering noise is a steeply varying medium–high-frequency modulation. At particle sizes less than 4 μm, the traditional dual-threshold method can effectively distinguish the target information from the smoke noise, which is the advantage of the LWIR laser compared to the NIR laser. For detecting lasers with high signal-to-noise ratios (SNRs), the method can achieve good target acquisition, by setting reasonable conventional thresholds, such as 0.7 times the peak intensity and 0.8 times the peak rising velocity. At low SNRs and steep intensity variation, the method can also achieve good target acquisition, by adaptively resetting new thresholds after filtering the detecting laser, such as 0.6 times the peak intensity and 0.6 times the peak rising velocity. The results of this paper will provide a reference for the performance improvement and refinement of the collimation system for wireless quantum communication networks in low visibility.

Iraq suffers from serious pollution with harmful particles that have important direct and indirect effects on human activities and human health. In this research, a system for detecting pollutants in the air was designed and manufactured using infrared laser technology. This system was used to detect the presence of pollutants in the dust storms that swept the city of Baghdad which could have a negative impact on human health and living organisms. The designed detection system based on the use of infrared laser (IR) with a wavelength of 1064 nm was used for the purposes of detecting pollutants based on the scattering of the laser beam from these pollutants. The system was aligned to obtain the best signal for the scattered rays, which were detected using a digital storage oscilloscope. These studies were conducted during the dust storms that occurred intensely in Baghdad in the months (April, May, June and July) of the year 2022. Where multiple samples were taken at different periods in these storms, measurements were also done during the storm. The types of polluting elements found in the dust of the storms are: carbon, bromine, chlorine, hydrocarbons alcohol, ether, hydroxyl group, carbon, C=C (aromatic ring), nitrogen dioxide (aromatic nitro), and carbon monoxide. The value ​​of dust pollutant concentrations is (125.67 mg. m-3).

Multispectral camouflage, especially for the infrared-microwave range, is an essential technology for the safety of facilities, vehicles, and humans. So far, it has been realized mainly by high infrared specular reflection and high microwave absorption. However, external infrared sources can expose the target through specular reflection; also, the heat production from microwave absorption can increase the infrared radiation. This work proposes a multispectral camouflage scheme based on hierarchical visible-infrared-microwave scattering surfaces to address these issues. The proposed device exhibits: (1) low infrared emissivity (ε 8–14 μm = 0.17) and low infrared specular reflectivity (R s 8–14 μm = 0.13), maintaining low infrared radiation and capability to overcome the presence of an external infrared source simultaneously; (2) high scattering in microwave range, with −10 dB radar cross section reduction bandwidth of 8–13 GHz, simultaneously achieving microwave camouflage and reducing the heat production; (3) tunability of color for visible camouflage. This work proposes a method to control scattering over visible-infrared-microwave bands, thereby introducing a new design paradigm for modern camouflage technology.

The dynamics of long polymer chains in the presence of nanoparticles have been investigated. The nanocomposites of interest were inspired by tire industry-like rubber materials and consisted of entangled polyisoprene linear chains mixed with chemically pre-treated silica nanoparticles. Combining rheology, dielectric spectroscopy, and neutron spin echo measurements, we measured the modification of the polymer chain dynamics from bulk state to high filler concentration over a broad range of time and length scales. We show that the end-to-end relaxation does not seem to be impacted, whereas the polymer dynamics is significantly slowed down at a very local scale in the presence of nano-fillers. In addition to this length scale dependent different dynamics, additional Neutron Spin Echo spectroscopy experiments and Small Angle Scattering on labelled polymer chains, irreversibly bound to the filler surface and re-dispersed in a fully deuterated matrix, revealed a negligible dynamical behavior of this particular population of localized chains in the rubber layer. The conformational statistics of these chains is that of self-avoiding walk train within a shell that is thinner than the size of the chain. To the best of our knowledge, this work is the first of its kind which measures the single chain form factor in the bound layer of chemically multi-linked chains to the filler surface.

Plane wave scattering characteristics of a conducting cylinder coated by a layer of metamaterial (MTM) having dispersive and lossy constitutive parameters – permittivity (ε) and permeability (μ) - with an intervening air gap is investigated by using the boundary-value technique. The backscattering cross section (BSCS) or the monostatic radar cross section (RCS) has been obtained for both the TM and the TE incident wave polarizations. Analysis based on a mathematical model, namely the Drude-Lorentz dispersion model, for the MTM coating shows that for a certain range of frequencies, the material may behave as either permeability- (or mu-) negative (MNG), permittivity- (or epsilon-) negative (ENG), both- (or double-) negative (DNG) or finally as both- (or double-) positive (DPS). The dispersive and lossy characteristics of these materials combined with the added features of an air gap (which can be practically realized by a layer of Styrofoam) seem to indicate that it is possible to achieve an extremely low radar echo width over a broad range of frequencies, particularly for the DNG type MTM. Further investigations on the total scattering cross section (TSCS) for the DNG type MTM, appear to demonstrate that near perfect broadband cloaking is possible with this geometry.

In [Opt. Lett. 38, 4023-4025 (2013)] the author predicted that the low coherent X-ray is hard to provide a high-resolution diffraction pattern from an object with a spatially periodic structure. This would severely restrict X-ray crystallography and its similar techniques. In this letter, we indicate that the Ghost diffraction technic takes advantage of the low coherence and may thus break through the bottleneck. Analytical formulae for calculating ghost diffraction patterns diffracted by the periodic structured media under any coherent state are derived.

Radio frequency identification (RFID) is a widely used wireless technology for contactless data exchange. Owing to international standardization and one-way security nature of the communication protocol, RFID tags, holding sensitive information, may be a subject to theft. One of the major security loopholes is the so-called far-field attack, where unauthorized interrogation is performed from a distance, bypassing the user’s verification. This loophole is a penalty of using a dipole-like RFID tag antenna, leaking wireless information to the far-field. Here we introduce a new concept of anapole-enabled security, prohibiting far-field attacks by utilizing fundamental laws of physics. Our design is based on radiationless electromagnetic states (anapoles), which have high near-field concentration and theoretically nulling far-field scattering. The first property enables performing data readout from several centimeters (near-field), while the second prevents attacks from a distance, regardless an eavesdropper’s radiated power and antenna gain. Our realization is based on a compact 3 cm high-index ceramic core–shell structure, functionalized with a thin metal wire and an integrated circuit to control the tag. Switching scheme was designed to provide a modulation between two radiation-less anapole states, blocking both up and down links for a far-field access. The anapole tag demonstrates more than 20 dB suppression of far-field interrogation distance in respect with a standard commercial tag, while keeping the near-field performance at the same level. The proposed concept might significantly enhance the RFID communication channel in cases, where information security prevails over cost constrains.

We present a multimer coupling classic harmonic oscillator model to reveal the scattering and photoluminescence (PL) properties of metallic nanoparticle chains. Taking particle number from 1 to 6 as examples, we compare the calculated spectra with the experimental ones from other researchers’ work, and they agree well with each other. Furthermore, scattering and PL properties are analyzed carefully varying with particle number n, coupling strength g, and effective free electron number N. Results indicates larger red-shift and smaller full width at half maximum (FWHM) of the scattering spectra with larger n or/and larger g. Particularly, the limitation of the red-shift is obtained in the limit of n→∞. Meanwhile, the splitting of PL modes increases as g increases, and the amplitudes are dependent on the excitation wavelength. This classic model is simple and shows a unified treatment for understanding the scattering and PL properties of multimer coupled systems.

In order to achieve a clear observation of the ultra-low brightness solar corona and provide a physical basis for forecasting space weather that seriously affects the human living environment, the stray-light suppression level becomes the key factor affecting the development of the coronagraph. In this study, a stray-light suppression method is adopted for Solar Corona Imager (SCI) which is a dual-waveband internally occulted reflecting coronagraph simultaneously and independently observing the inner corona in the HI Lyman-alpha (121.6 ± 10 nm) line and white-light (700.0 ± 40 nm) wavebands with a field-of-view (FOV) from 1.1 to 2.5 R⊙ (R⊙ stands for the mean solar radius). The scattered stray-light from the primary mirror, including the surface errors, cosmetic defects, and particulate contamination, is analyzed and suppressed, and the corresponding scattering models are established for simulation based on the laboratory testing. The stray-light measurement results for SCI in the laboratory show that the stray-light level can be suppressed to the order of 10−8 B⊙ at 2.5 R⊙ (B⊙ is the mean brightness of the solar disk) in the white-light (WL) band, which is consistent with the stray-light level obtained by simulation and verifies the modeling and simulation.

The study of an optical beam interacting with material structures is a fundamental of nanophotonics. Computational electromagnetic solvers facilitate the rapid calculation of the scattering from material structures with arbitrary geometry and complexity, but have limited efficiency when employing structured excitation fields. We have developed a post-processing method and package that can efficiently calculate the full three-dimensional electric and magnetic fields for any optical beam incident on a particle or structure with at least one axis of continuous rotational symmetry, called an axisymmetric body (such as a sphere, cylinder, cone, torus or surface). Provided an initial batch of plane wave simulations is computed, this open-source package combines data from computational electromagnetic solvers in a post-processing fashion using the angular spectrum representation to create arbitrarily structured beams, including vector vortex beams. Any and all possible incident beams can be generated from the initial batch of PWSs, without the need for further simulations. This allows for efficiently performing parameter sweeps such as changing the angle of illumination or translating the particle position relative to the beam, all in post-processing, with no need for additional time-consuming simulations. We demonstrate some applications by numerically calculating optical force and torque maps for a spherical plasmonic nanoparticle in a tightly focused Gaussian beam, a plasmonic nanocone in an azimuthally polarised beam and compute the fields of a non-paraxial Laguerre–Gaussian vortex beam reflecting on a multilayered surface. We believe this package, called BEAMS, is a valuable tool for rapidly quantifying electromagnetic systems that are beyond traditional analytical methods.

Optical properties of coupled metallic nanoparticles (MNPs) have been widely reported due to their unique characteristics such as peak shift/splitting of the coupling spectra and electromagnetic enhancement at subwavelength scale, etc. In a previous work, we have investigated the coupling spectra of two coupled MNPs with parallel polarized excitation. In this study, we investigate the vertical polarization case in detail. Different from the parallel one, the vertical one has its unique properties: (a) three coupling coefficients; (b) positive coupling terms in the coupling equations; (c) blue-shifts of the peaks with the increasing coupling strength for identical MNPs spectra, including scattering, absorption, and photoluminescence (PL). The model shows that for the two resonant MNPs, the spectra reveal only one mode that blue shifts as the coupling strength increases; while for the two non-resonant MNPs, the spectra reveal two splitting modes, one of which blue shifts and the other of which red shifts as the coupling strength increases. The relative intensity of the two modes varies with the coupling strength. Furthermore, the PL efficiency (relative to the scattering) is about the order of 10 ^−2 . Comparison with published experimental results shows the validity of this model. This work provides a deeper understanding on the optical properties of coupled MNPs and is beneficial to relevant applications.

Celestial objects such as stars and planets might be able to capture a large amount of dark matter particles through dark matter-nucleon scattering. Many previous studies have considered different celestial objects such as the Sun and the Earth as natural dark matter detectors and obtained some stringent bounds of the dark matter-nucleon scattering cross section. In this study, we use the ∼10 MeV electron neutrino flux limits obtained by the Super-Kamiokande experiment and consider the Earth as a large natural dark matter detector to constrain the dark matter-nucleon scattering cross section. We show that this method can generally get more stringent limits. For certain ranges of dark matter mass annihilating via the bb¯ channel, the limits of cross section for the isospin-independent scattering and proton-only scattering could be more stringent than that obtained in the PICO direct-detection experiment.

Most simulations involving metamaterials often require complex physics to be solved through refined meshing grids. However, it can prove challenging to simulate the effect of local physical conditions created by said metamaterials into much wider computing sceneries due to the increased meshing load. We thus present in this work a framework for simulating complex structures with detailed geometries, such as metamaterials, into large Finite-Difference Time-Domain (FDTD) computing environments by reducing them to their equivalent surface impedance represented by a parallel-series RLC circuit. This reduction helps to simplify the physics involved as well as drastically reducing the meshing load of the model and the implicit calculation time. Here, an emphasis is made on scattering comparisons between an acoustic metamaterial and its equivalent surface impedance through analytical and numerical methods. Additionally, the problem of fitting RLC parameters to complex impedance data obtained from transfer matrix models is herein solved using a novel approach based on zero crossings of admittance phase derivatives. Despite the simplification process, the proposed framework achieves good overall results with respect to the original acoustic scatterer while ensuring relatively short simulation times over a vast range of frequencies. [ABSTRACT FROM AUTHOR]

We study the interaction of a single photon in a surface plasmon polariton mode with multiple atoms. We propose a system of two atoms to achieve a tunable scattering from subscattering to superscattering regimes by changing the angle of the incident photon. We also demonstrate a perfect electromagnetically-induced transparency using two atoms with two-level structures. The proposed framework is efficiently scalable to a system with a large number of atoms and opens up the possibility of designing novel atom-based optical devices. We design an atomically thin parabolic mirror to focus single photons and form a quantum mirage in a cavity built from atoms.

Ultrasound imaging of the liver is an everyday, worldwide clinical tool. The echoes are produced by inhomogeneities within the interrogated tissue, but what are the mathematical properties of these scatterers? In theory, the spatial correlation function and the backscatter coefficient are linked by a Fourier transform relationship, however direct measures of these are relatively rare. Under the hypothesis that the fractal branching vasculature and fluid channels are the predominant source of scattering in normal tissues, we compare theory and experimental measures of the autocorrelation function, the frequency dependence of scattering, and fractal dimension estimates from high contrast 3D micro-CT data sets of rat livers. The results demonstrate a fractal dimension of approximately 2.2 with corresponding power law estimates of autocorrelation and ultrasound scattering. These results support a general framework for the analysis of ultrasound scattering from soft tissues.

Abstract This paper presents a physically valid quasi-ballistic drain current model applicable for nanoscale symmetric Double Gate (SDG) MOSFETs. The proposed drain current model includes both diffusive and ballistic transport phenomena. The model considers the important positional carrier scattering dependency effect near the source region described in terms of transmission and reflection co-efficients related to the scattering theory. The significance of carrier transport near the bottleneck source region is illustrated where the carriers diffuse into the channel at a relatively lower velocity before accelerating ballistically. The results obtained demonstrate carrier scattering dependency at the critical layer defined near the low field source region on the drain current characteristics. The proposed model partly evolves from Natori’s ballistic bulk MOSFET model that is modified accordingly to be valid for a symmetric Double Gate MOSFET in the nanoscale regime. Carrier degeneracy and Fermi–Dirac statistics are included in the work so as to justify the complete physicality of the model. The model is further extended and is shown to be continuous in terms of terminal charges and capacitances in all regions of operation. A comparative analysis is also done between the proposed quasi-ballistic model and a hypothetical complete ballistic device.

The paper deals with the application of the method of eigenfunctions of the S-matrix to the problem of two zero range potentials and continues our study of photodetachment, begun in a previous paper (Devdariani, Dadonova 2018). In the case under consideration the eigenfunctions of specific parity depend on two phases that lead to the explicit expressions for the characteristics of scattering and make it possible to construct the proper sets of wave functions for the problems of scattering and photodetachment. An interesting feature of the problem is that the two phases can coincide, which leads to a resonance in the transmission coefficient.

Scattering of excitons by free carriers is a phenomenon, which is especially important when considering moderately to heavily doped semiconductors in low-temperature experiments, where the interaction of excitons with acoustic and optical phonons is reduced. In this paper, we consider the scattering of excitons by free carriers in monolayer hexagonal boron nitride encapsulated by a dielectric medium. We describe the excitonic states by variational wave functions, modeling the electrostatic interaction via the Rytova–Keldysh potential. Making the distinction between elastic and inelastic scattering, the relevance of each transition between excitonic states is also considered. Finally, we discuss the contribution of free carrier scattering to the excitonic linewidth, analyzing both its temperature and carrier density dependence.

Ultrasonic Non-Destructive Testing (NDT) methods are broadly used for detection and characterization/imaging of cracks. Simulation is of great interest for designing such NDT methods. To model the ultrasonic 3D response of a crack, ultrasonic high frequency asymptotic (semi-analytical) models (such as the Physical Theory of Diffraction—PTD) are known to provide accurate predictions for most classical NDT configurations, and 3D numerical models have also emerged more recently. The aim of this paper is to carry out for the first time an experimental and theoretical comparison of 3D models for ultrasonic NDT of embedded cracks in 3D configurations. Semi-analytical models and a hybrid 3D FEM strategy—combining high-order spectral Finite Elements Method (FEM) for flaw scattering and an asymptotic ray model for beam propagation—have been compared. Both numerical validations and comparisons between simulation and experiments prove the effectiveness of PTD in numerous configurations but validate and demonstrate the improvement provided by the 3D hybrid code, notably for small flaws compared to the wavelength and for shear waves.

The subthreshold swing (SS) of a field-effect transistor (FET) is given by the body factor multiplied by the transport factor and has a limit of 60 mV ⋅ dec−1 at room temperature in the case of the MOSFET. To break this SS limit, the negative-capacitance FET (NC-FET) lowers the body factor by using a ferroelectric film in the gate stack, whereas the cold source FET (CS-FET) and the Dirac source FET (DS-FET) lower the transport factor by introducing an electronic bandgap or manipulating the density of states in the injecting source. In this work, we theoretically and computationally investigate the possibility of FETs with both NC and CS/DS so that both the body and transport factors are lowered simultaneously. The new device physics of the negative-capacitance CS-FET (NCCS-FET) is numerically investigated for 2-D monolayer black phosphorus (ML-BP) FETs with the Hf0.5Zr0.5O3 ferroelectric material in the gate stack. The device characteristics of six different FETs, the conventional MOSFET, CS-FET, DS-FET, NC-FET, NCCS-FET, and NCDS-FET are calculated and compared. Overall, the NCCS-FET achieves an average SS of 30.1 mV ⋅ dec−1 and a minimum SS as low as 7.21 mV⋅ dec−1; its ON–OFF ratio is about four orders of magnitude higher than that of a conventional MOSFET. The combined effects of NC and CS more efficiently decrease power dissipation. [ABSTRACT FROM AUTHOR]