bluuebunny/crossref_metadata_2025 huggingface dataset:
Final report on EURAMET key comparison EURAMET.M.D-K2.1 (1522)
Authors: Prochaska L , Rauch J , Furtado A , Benga F , Bartos P , Bebic J , Lenard E , Alisic S , Alic A , Neuvonen P T , Sariyerli G S , Akcadag Ü Y
Published: March 2024

Main text

The key comparison EURAMET.M.D-K2.1 (1522) on the density of liquids determined by hydrostatic weighing was organized and carried out within the framework of the EMPIR project 17RPT02 "rhoLiq". Density measurements of liquids are mainly performed by laboratories calibrating or checking liquid density measuring instruments such as oscillation-type density meters. Another aim of this comparison was to establish traceability for liquid density measurements at emerging National Metrology Institutes (NMIs) to enable them to provide high-level measurement and calibration services for national stakeholders, e.g. food, chemical, pharmaceutical and petroleum industries. The results of this comparison can be used to claim calibration and measurement capabilities (CMCs).

Most European emerging NMIs in this project had not yet participated in comparisons or obtained unsatisfactory results, or the uncertainty had a magnitude that was not fit for purpose.

BEV (Austria) piloted this comparison, supported by PTB (Germany).

Samples of deuterated water, tetrachloroethylene and oil of high viscosity were measured in the temperature range from 5 °C to 20 °C at atmospheric pressure by hydrostatic weighing for this comparison.

The coronavirus pandemic caused delays in this key comparison's proposed initial schedule. Measurements were performed in 2021. The reference values of the key comparison were linked to CCM.D-K2 for PTB and EURAMET.M.D-K2 for BEV.

To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.

The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Final report of APMP.AUV.V-S1: supplementary comparison on calibration of laser tachometers using mechanical generators
Authors: Qiao Sun , Lei Du , Shan Cui , Jianqiang Mou
Published: March 2024

Main text

This is the final report for APMP supplementary comparison APMP.AUV.V-S1 in the area of 'vibration' (quantity of rotational speed). The aim of this comparison was to compare primary measurements of rotational speed in the range from 10 r/min to 99 999 r/min. Two Metrology Institutes from APMP have participated in the comparison with National Institute of Metrology, P.R. China as pilot lab. Both laboratories used mechanical generators as standard equipment and provided their calibration results, which were all consistent within their declared expanded uncertainties for the measurement results except for 10 r/min. Both participants contributed to the SCRVs calculated for thirteen rotational speed comparison values. NMC was not consistent within their declared expanded uncertainties at 10 r/min. Further improvements of their calibration devices and uncertainty evaluations will provide more accurate and reliable measurement results in the future.

To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.

The final report has been peer-reviewed and approved for publication by the CCAUV, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Hybrid geometrodynamics: a Hamiltonian description of classical gravity coupled to quantum matter
Authors: Alonso J L , Bouthelier-Madre C , Clemente-Gallardo J , Martínez-Crespo D
Published: March 2024

We generalize the Hamiltonian picture of general relativity coupled to classical matter, known as geometrodynamics, to the case where such matter is described by a quantum field theory in curved spacetime, but gravity is still described by a classical metric tensor field over a spatial hypersurface and its associated momentum. Thus, in our approach there is no non-dynamic background structure, apart from the manifold of events, and the gravitational and quantum degrees of freedom have their dynamics inextricably coupled. Given the Hamiltonian nature of the framework, we work with the generators of hypersurface deformations over the manifold of quantum states. The construction relies heavily on the differential geometry of a fibration of the set of quantum states over the set of gravitational variables. An important mathematical feature of this work is the use of Minlos’s theorem to characterize Gaussian measures over the space of matter fields and of Hida distributions to define a common superspace to all possible Hilbert spaces with different measures, to properly characterize the Schrödinger wave functional picture of QFT in curved spacetime. This allows us to relate states within different Hilbert spaces in the case of vacuum states or measures that depend on the gravitational degrees of freedom, as the ones associated to Ashtekar’s complex structure. This is achieved through the inclusion of a quantum Hermitian connection for the fibration, which will have profound physical implications. The most remarkable physical features of the construction are norm conservation of the quantum state (even if the total dynamics are non-unitary), the clear identification of the hybrid conserved quantities and the description of a dynamical backreaction of quantum matter on geometry and vice versa, which shall modify the physical properties the gravitational field would have in the absence of backreaction.
Entanglement dynamics of two non-Hermitian qubits
Authors: Zhang Yi-Xi , Zhang Zhen-Tao , Wei Xiao-Zhi , Liang Bao-Long , Mei Feng , Yang Zhen-Shan
Published: March 2024

The evolution of entanglement in a non-Hermitian quantum system may behave differently compared to its Hermitian counterpart. In this paper, we investigate the entanglement dynamics of two coupled and driven non-Hermitian qubits. Through calculating the concurrence of the system, we find that the evolution of the bipartite entanglement manifests two distinct patterns in the parameter space. In the low non-Hermiticity regime, the concurrence oscillates significantly, while in the opposite regime the same quantity would trend to a stable value. We attribute this phenomenon to parity-time (

PT

) symmetry phase transition. We also study the effect of decoherence on the entanglement dynamics. Our work provides a method to stabilize entanglement by exploiting non-Hermiticity.
Application of a metallic-magnetic calorimeter for high-resolution x-ray spectroscopy of Fe at an EBIT
Authors: Herdrich M O , Hengstler D , Allgeier S , Friedrich M , Fleischmann A , Enss C , Bernitt S , Morgenroth T , Trotsenko S , Schuch R , Stöhlker Th
Published: March 2024

In this work, we present an experiment conducted at the S-EBIT-I ion trap of GSI. It involved the study of ion-electron collisions of Fe and Ba ions in various charge states with the electron beam. Characteristic x-ray radiation emitted during the continuous interaction was recorded utilizing an energy-dispersive maXs-30 detector based on metallic-magnetic calorimeter (MMC) technology. Optimizations to the applied sensitivity-drift correction and energy calibration procedures significantly improved the achieved energy resolution compared to previous applications of a similar detector. This made it possible to individually resolve and identify overlapping x-ray lines of iron and barium in a wide spectral range. As a demonstration of the outstanding detector performance, we used the recorded spectral data to extract an estimate of the charge state distribution of Fe ions in the trap. This experiment campaign marks an important milestone in the ongoing effort to enable the deployment of MMC detectors for future high-precision measurements in fundamental physics experiments.
Interference effects in Compton scattering of keV photons at H
2+
: a nonrelativistic analytical approach
Authors: Dieng Matabara , Bachau Henri
Published: March 2024

In this paper we study interference effects in Compton scattering at molecule by keV photons. As a test case we investigate the molecular system H

2
+

at the equilibrium internuclear distance and in the dissociative channel. The initial molecular wavefunction is described as a linear combination of atomic orbitals centered on each nucleus. The final continuum state is a two-centre continuum Coulomb wavefunction. Using these approximations, we obtain an analytical form for the Compton scattering fully differential cross section. We investigate the molecular effects at various internuclear distance for an incident photon energy close to 2.1 keV. The relative contribution of the

A
⋅
P

and
A

2 coupling terms in the Compton scattering magnitude is discussed (where
P
is the electron momentum operator and
A
the vector potential of the field). We focus on Cohen-Fano type interference effects, as the ones observed in the photoionization of molecules.
Robust magnetism and crystal structure in Dirac semimetal EuMnBi2 under high pressure
Authors: Jose Greeshma C , Xie Weiwei , Lavina Barbara , Zhao Jiyong , Alp Esen E , Zhang Dongzhou , Bi Wenli
Published: March 2024

Dirac materials offer exciting opportunities to explore low-energy carrier dynamics and novel physical phenomena, especially their interaction with magnetism. In this context, this work focuses on studies of pressure control on the magnetic state of EuMnBi2, a representative magnetic Dirac semimetal, through time-domain synchrotron Mössbauer spectroscopy in 151Eu. Contrary to the previous report that the antiferromagnetic order is suppressed by pressure above 4 GPa, we have observed robust magnetic order up to 33.1 GPa. Synchrotron-based x-ray diffraction experiment on a pure EuMnBi2 sample shows that the tetragonal crystal lattice remains stable up to at least 31.7 GPa.
Exploring the effect of a phenomenological teaching-learning sequence on lower secondary school students’ views of light polarisation
Authors: Tóth Kristóf , Michelini Marisa , Bitzenbauer Philipp
Published: March 2024

The wave model of light in general, and the phenomenon of light polarisation in particular, are difficult topics for secondary school students. Prior research has indicated that a model-free phenomenological teaching approach may be fruitful in helping students overcome some of the widespread learning obstacles. These phenomenological approaches are characterised by their departure from abstract and mechanistic models of light, opting instead to prioritise students’ observations throughout the exploration of phenomena and experiments, unburdened by mathematical formalism or theoretical models. In this paper, we present a three-lessons phenomenological teaching-learning sequence on light polarisation. We evaluated of the teaching concept in classroom practise and analysed ways of thinking about light polarisation among N = 110 students (aged 12–14 years) who participated in the intervention using qualitative content analysis of free-text responses. The results provide preliminary empirical evidence that the presented instructional approach can contribute to the development of a qualitative understanding of polarisation among learners in introductory optics.
Experimental validation of the brachistochrone curve
Authors: Azevedo Silva Pessôa Matheus , Kljunak Jelena , Zhivaljevikj Elena , Smilevska Mihaela
Published: March 2024

We built a simple, cheap and accessible experiment to study the motion of spherical beads through three different curves, one of them being the curve of fastest descent, or brachistochrone. Despite the absence of a no-friction constraint and the rolling of the beads, our experimental findings consistently support the conclusion that the brachistochrone path remains the fastest. We perform a numerical simulation to confront with experiments and obtain that the values are in agreement, with

t

t
h
e
o
r
y

=
0.237

s, and

t
‾

b
r
a
q

=
0.25
±
0.03

s. This simple system not only serves as a practical demonstration of minimization principles but can also inspire and engage students in high schools and colleges interested in physics.
Identifying quantum effects in seeded QED cascades via laser-driven residual gas in vacuum
Authors: Guo Yinlong , Geng Xuesong , Ji Liangliang , Shen Baifei , Li Ruxin
Published: March 2024

The discrete and stochastic nature of the processes in the strong-field quantum electrodynamics (SF-QED) regime distinguishes them from classical ones. An important approach to identifying the SF-QED features is through the interaction of extremely intense lasers with plasma. Here, we investigate the seeded QED cascades driven by two counter-propagating laser pulses in the background of residual gases in a vacuum chamber via numerical simulations. We focus on the statistical distributions of positron yields from repeated simulations under various conditions. By increasing the gas density, the positron yields become more deterministic. Although the distribution stems from both the quantum stochastic effects and the fluctuations of the environment, the quantum stochastic effects can be identified via the width of the distribution and the exceptional yields, both of which are higher than the quantum-averaged results. The proposed method provides a statistical approach to identifying the quantum stochastic signatures in SFQED processes using high-power lasers and residual gases in the vacuum chamber.
Unveiling surface and bulk contributions in temperature dependent THz emission from Bi2Te3
Authors: Nivedan Anand , Kumar Sunil
Published: March 2024

We report evolution of the pulsed terahertz (THz) emission from Bi2Te3 topological insulator in a wide temperature range, where an interplay between the topological surface and bulk contributions can be addressed in a distinguishable manner. A circular photogalvanic effect-induced topological surface current contribution to THz generation can be clearly identified in the signal, otherwise, overwhelmed by the hot carrier decoherence in the bulk states. With the decreasing temperature, an initial sharp increase in the topological surface THz signal is observed before it attains a constant value below ∼200 K. The scattering channels between topological surface and bulk regions via carrier-phonon scattering are dominantly active only above the bulk-Debye temperature of ∼180 K, and the temperature-independent behavior of it at lower temperatures is indicative of robust nature of topological surface states. THz emission due to ultrafast photon-drag current in the bulk states is almost independent of temperature in the entire range, while the combined photo-Dember and band-bending effects induced photocurrent is doubled at 10 K.
Large tunneling magnetoresistance and its high bias stability in Weyl half-semimetal based lateral magnetic tunnel junctions
Authors: Tan Jianing , Yang Guowei , Ouyang Gang
Published: March 2024

Magnetic tunnel junctions (MTJs) based on novel states of two-dimensional (2D) magnetic materials will significantly improve the value of the tunneling magnetoresistance (TMR) ratio. However, most 2D magnetic materials exhibit low critical temperatures, limiting their functionality to lower temperatures rather than room temperature. Moreover, most MTJs experience the decay of TMR ratio at large bias voltages within a low spin injection efficiency (SIE). Here, we construct a series of MTJs with Weyl half-semimetal (WHSM, e.g. MnSiS3, MnSiSe3, and MnGeSe3 monolayers) as the electrodes and investigate the spin-dependent transport properties in these kind of lateral heterojunctions by employing density functional theory combined with non-equilibrium Green’s function method. We find that an ultrahigh TMR (∼109%) can be obtained firmly at a small bias voltage and maintains a high SIE even at a large bias voltage, and MnSiSe3 monolayer is predicted to exhibit a high critical temperature. Additionally, we reveal that the same structure allows for the generation of fully spin-polarized photocurrent, irrespective of the polarization angle. These findings underscore the potential of WHSMs as candidate materials for high-performance spintronic devices.
Fisher information rates in sequentially measured quantum systems
Authors: O’Connor Eoin , Campbell Steve , Landi Gabriel T
Published: March 2024

We consider the impact that temporal correlations in the measurement statistics can have on the achievable precision in a sequential metrological protocol. In this setting, and for a single quantum probe, we establish that it is the transitions between the measurement basis states that plays the most significant role in determining the precision, with the resulting conditional Fisher information being interpretable as a rate of information acquisition. Projective measurements are shown to elegantly demonstrate this in two disparate estimation settings. Firstly, in determining the temperature of an environment and, secondly, to ascertain a parameter of the system Hamiltonian. In both settings we show that the sequential estimation approach can provide a useful method to enhance the achievable precision.
Predicting the AC conductivity of semiconductor composition thin films using ANFIS model; an integrated experimental and theoretical approach
Authors: Mohamed R A , Atyia H E
Published: March 2024

The current research investigates the conductivity σ

AC
of glassy As4Ge24Te72 thin films through a combined experimental and theoretical approach. It sheds light on the complex relationship between σ

AC
, frequency, temperature, and film thickness. Analysis reveals that σ

AC
follows ω
r law and exhibits hopping behavior. To effectively model and predict σ

AC
, an adaptive neuro-fuzzy inference system (ANFIS) is utilized. The ANFIS model successfully simulates the experimental data, showing high accuracy. Additionally, the prediction of experimentally measured values of σ

AC
is processed as a testing step and provides acceptable results. That enables ANFIS to enlarge the scale and complete the missing parts in the trained datasets by predictions for unmeasured σ

AC
values. The ANFIS network was built using MATLAB-R2017a. It consists of two inputs (frequency and temperature) and one output (AC conductivity). The precision is confirmed by calculating the modeling errors across the training process. The mean absolute errors MAE through the modeling process are not exceeding

10

−
5

.

This average error value demonstrates the model’s effective ability. The alignment between experimental and ANFIS modeling results open up exciting possibilities for future research. By predicting the properties of the understudy material using ANFIS model, we can pave the way for more compact and efficient electrical devices.
Spatial shifts of reflected rotating elliptical Gaussian beams from surface phonon polaritons in hyperbolic materials
Authors: Li Yu-Bo , Song Hao-Yuan , Wang Xiang-Guang , Zhang Qiang , Fu Shu-Fang , Wang Xuan-Zhang
Published: March 2024

The effect of surface phonon polaritons (SPhPs) on Goos-Hänchen (GH) and Imbert-Fedorov (IF) shifts of reflected rotating elliptical Gaussian beams (REGBs) is investigated in the Otto configuration with a naturally hyperbolic material (NHM) substrate. The spatial shifts are enhanced significantly and adjusted by tuning the REGBs and the optical axis orientation of NHM. The magnitude of GH and IF shifts is easily evaluated by timing the elliptical parameter

b

0

2

on the basis of the spatial shift at

b

0

=
1.0

when

η
(
=

a

0

/

b

0

)
≥
2.0
.

The attenuation total reflection (ATR) spectra are simulated for a hexagonal boron nitride (hBN) substrate. To better understand the impact of SPhPs on the GH and IF shifts, the dispersion curves of SPhPs are calculated. The features of GH and IF shifts around SPhPs can be observed through the frequency scanning along the dispersion curves at a fixed incident angle. The comparison between the ATR spectra and the dispersion curves demonstrates that the enhancement of GH and IF shifts with higher reflection always occurs in the reststrahlen bands (RBs) of NHM once SPhPs are excited. In RB-I, the magnitudes of GH and IF shifts attributable to the SPhPs are located between the peak and dip of a shift curve within a very narrow frequency region. However, in RB-II, the positive maximum values of GH and IF shifts just coincide with the SPhPs. As a result, it is predicted that a relatively large spatial shift will be observed along the frequency scanning line. The large shifts accompanied by the higher reflection may show potential applications in optical or optoelectronic technologies.
Characterizing the thickness and temperature dependence of elastic modulus in polymer films using picosecond ultrasonics
Authors: Yan Jinyu , Li Lian , Zeng Yantao , Tu Xinhao , Li Chuanwei , Wang Zhiyong
Published: March 2024

Polymer nanofilms have found extensive applications in fields such as medical science and microelectronics, making the exploration of their mechanical properties highly significant. In this study, we examine the dependency of the out-of-plane elastic modulus of polymer films on both thickness and temperature, utilizing picosecond ultrasonics. Multiple acoustic modes of a polymer film are employed to measure its elastic modulus with heightened precision. Measurements are conducted on samples with different thicknesses and at different temperatures. The results indicate that the modulus of polymer nanofilms strongly depends on both thickness and temperature. For polymethyl methacrylate (PMMA) films with a thickness of less than 81 nm, the modulus determined exhibits a decrement correlating with thickness and is quantifiably inferior to the analogous bulk value. Additionally, as the temperature rises, the elastic modulus declines at clearly varying rates, which are described by two distinct modulus-temperature coefficients.
Gap solitons in quasi-1D Bose–Einstein condensate with three-body interactions under PT symmetry
Authors: Ma Jinping , Wang Qingqing , Tu Pu , Shao Kaihua , Zhao Yuexing , Su Ruiming , Zhao Xi , Xi Baolong , Shi Yuren
Published: March 2024

The existence and stability of gap solitons in a quasi-one-dimensional Bose–Einstein condensate with three-body interactions loaded in a PT-symmetric potential are investigated numerically. Under the mean-field approximation, the dynamical behaviors of the system are described by a cubic-quintic Gross–Pitaevskii equation. Firstly, we obtained the band-gap structures via linearizing the GPE. The PT-symmetric of the system will be broken if the magnitude of the imaginary part of the external potential exceeds a critical value. Secondly, various of gap solitons were found by the Newton-Conjugate-Gradient method. Finally, the stability properties of gap solitons were investigated through the linear stability analysis and the direct long-time nonlinear dynamical evolution. The results indicated that the stability of on-site and off-site solitons was remarkably influenced by three-body interactions. There exists unstable on-site gap solitons when the PT-symmetric potential is taken into account. Additionally, the magnitude of the imaginary part of the potential also affects the profile and stability of the gap solitons. When it increases, the symmetry of the solitons will be broken.
First integrals, conserved vectors of nonlinear partial difference equations
Authors: Hussain Akhtar , Kara A H , Zaman F D
Published: March 2024

We perform a symmetry analysis of some nonlinear partial difference equations (nP △ Es), where the discrete version is obtained using some discretization approach. The discrete versions of the wave, diffusion, Fisher and Huxley equations are the subject of this research. At first, the initial invariance approach is the Lie symmetry approach. The first integrals technique that Hydon introduced to be used with discrete ordinary difference equations (O △ Es) serves as our inspiration in this situation. We develop a similar technique for generating the first integral vectors of the nP △ Es without recourse to symmetry generators.
A computational strategy for nonlinear time-fractional generalized Kawahara equation using new eighth-kind Chebyshev operational matrices
Authors: Ahmed H M , Hafez R M , Abd-Elhameed W M
Published: March 2024

This paper presents a new method to numerically solve the nonlinear time-fractional generalized Kawahara equations (NTFGKE) with uniform initial boundary conditions (IBCs). A class of modified shifted eighth-kind Chebyshev polynomials (MSEKCPs) is introduced to satisfy the given IBCs. The proposed method is based on using the operational matrices (OMs) for the ordinary derivatives (ODs) and the fractional derivatives (FDs) of MSEKCPs. These OMs are employed together with the spectral collocation method (SCM). Our presented algorithm enables the extraction of efficient and accurate numerical solutions. The convergence of the suggested method and the error analysis have been developed. Three numerical examples are presented to demonstrate the applicability and accuracy of our algorithm. Some comparisons of the presented numerical results with other existing ones are offered to validate the efficiency and superiority of our approach. The presented tables and graphs demonstrate that the proposed approach produces approximate solutions with high accuracy.
Influence of Cu doping on the functionality of spray coated SnS2 thin films and its photocatalytic degradation of dyes and antibacterial activity
Authors: Radja Imane , Nebatti Ech-Chergui Abdelkader , Zekri Atef , Rahman Ashmalina , Khane Yasmina , Bennabi Farid , Kadari Ali Sadek , Guezzoul M’hamed , Popa Adriana , Driss-Khodja Kouider , Aïssa Brahim , Amrani Bouhalouane , Khan Mohammad Mansoob
Published: March 2024

Tin sulfide (SnS2) is a material known for its effective photocatalytic activity due to its affordability and wide light spectrum response. To enhance and optimize its optical and chemical characteristics, doping is a straightforward approach that can improve its photocatalytic efficiency. This work focuses on the effect of Cu doping on the structural, optical, and photocatalytic properties of the thin films prepared by the spray-coating approach. XRD confirms the hexagonal SnS2 structure. As the amount of Cu added increases, the crystallite size decreases while dislocation density rises. The XPS findings show that a low concentration of copper (2%) within the SnS2 thin films exhibits both high solubility and exclusively a monovalent state, in contrast to the 4% concentration. The effective band gap is in the range of 1.9–2.2 eV. SEM image reveals a variety of morphologies, and the porosity is reduced with increasing Cu doping. Furthermore, the FTIR study confirms the Sn-S bond present at 753 cm−1. EPR studies reveal the existence of sulfur vacancies in Cu-doped SnS2. Mechanical properties were also affected, with an observed decrease in microhardness as the dopant concentration increased. The photocatalytic activity of the samples is studied by photocatalytic degradation of malachite green and Congo red dyes under visible light irradiation. Additionally, their antibacterial effect against Escherichia coli was examined. This study shows that an optimal amount of Cu doping can significantly increase the photocatalytic performance of SnS2 for efficiently decomposing organic pollutants and enhancing antibacterial activities.
Jovian Magnetosheath Turbulence Driven by Whistler
Authors: Dwivedi N K , Singh S , Khodachenko M L , Sasunov Yu L , Kovács P , Kislyakova K G , Kis A
Published: March 2024

Jupiter’s magnetosheath is a natural yet complex laboratory for analyzing compressible plasma turbulence. Recent observations by the Juno mission provide a promising opportunity for the first time to reckon the energy cascade rate in the magnetohydrodynamic scales in the vicinity of Jupiter’s space. In the present work, a two-dimensional model is constructed for a whistler wave that is nonlinearly coupled with a wave magnetic field via ion density perturbation. The dynamics of whistler wave propagating in the direction of the magnetic field are derived within the limit of the two-fluid modeling approach. The magnetic field localization along with magnetic field spectra and spectral slope variations are estimated to realize the turbulence generation and energy cascade from large to small scales in the Jovian magnetosheath region. The simulated magnetic field spectrum in the wave number (in the unit of ion inertial length ρ

i
) consists of turbulence in the inertial range with a spectral slope of −1.4 and a spectral knee at k
ρ

i
= 1. Subsequently, the spectral slope increases to −2.6 and the spectrum becomes steeper. The simulated magnetic field spectrum in the wave number is further translated into the frequency domain using the whistler wave dispersion relation and by considering the Taylor frozen-in condition. The analytically estimated magnetic field spectrum slopes, i.e., −1.8 and −4.2 at low and high frequencies are further compared with recent Juno mission observations. The comparison further affirms the existence of Kolmogorov scaling, a spectral knee, and steepening in the spectrum at high frequencies. Furthermore, it is found that the two-fluid model can reasonably simulate the turbulence effects in Jovian magnetosheath in terms of magnetic field spectral distribution in wave number and frequency domains.
The construction of quantum network model based on formalized theory
Authors: Xiong Si-Yu , Bai Ming-Qiang , Mo Zhi-Wen
Published: March 2024

With the rapid development of quantum communication, various types of quantum communication protocols emerge one after another, and their number has been very large. Usually a quantum communication protocol is expressed in long words. Formalized processing of quantum communication protocol can simplify its expression mode, which is conducive to fast reading and selection of required protocols according to actual application requirements. In this paper, quantum communication protocols that use entangled particles as quantum channels to transmit known or unknown quantum states are classified based on classification of set, and the classified protocols are described in formalized language. A new quantum communication network model is constructed by using the formalized quantum communication protocol.
Preparation and structure investigation of polyethylene terephthalate polyester reinforced Ni0.5Zn0.5Fe2O4 nanoparticles for gamma ray shielding performance
Authors: Almeshari Meshari , Sallam Fawzy Hammad , Tharwat Mohamed , Alzamil Yasser , Salih Mohammed , Alshoumr Bader , Alyahyawi Amjad , El-Taher Atef
Published: March 2024

Defects of high atomic materials gamma-ray shielding such as low chemical stability, low mechanical properties, and heaviness lead us to investigate other light and flexible materials such as polymers. Polymer-doped nanosized materials are the most frequently examined materials. In this study, polyethylene terephthalate [(C10H8O4)n] was doped with Ni0.5Zn0.5Fe2O4 nanoparticles up to 40 wt% (0.0, 10.0, 20.0, 40.0 wt%) prepared by Sol–Gel auto-combustion method with the help of Gelatin. The polyester/Nanofiller composite structures were identified using x-ray photoelectron spectroscopy, x-ray diffraction, Scanning, and Transmission electron microscope as well as density measurements. x-ray photoelectron spectroscopy confirmed the successful doping of nanofiller in the polyester structure as Zn signals appear in the atomic composition and Fe signals appear in the deconvolution of the peaks. x-ray diffraction, transmission, and scanning electron microscope display the same result. x-ray diffraction graph information with the Scherer equation offered the crystal size of the composite (26 nm). Polyester/nanofiller samples were scanned against gamma-ray and experimental shielding factors were computed using a narrow beam transmission technique with sodium iodide detector and two-point sources Cs-137 and Co-60. Experimental Linear and mass attenuation coefficient values swelled as percentages of nanofiller increased in the polyester structure. Experimental Mass attenuation values were compared with theoretical ones estimated from XCOM and Physics-X programs. The difference between them does not exceed 12% which is acceptable as the x-ray photoelectron spectroscopy atomic composition utilized in the theoretical data calculation does not reveal Ni signals. This may occur at the depth of the composite structure. Finally, the half-value layer, the Tenth value layer, and the Mean free path are determined experimentally, and their values are reduced as the nanofiller doping percentage rises in the structure. This result confirms the efficiency of nanofiller addition to the polyester structure to attenuate gamma-ray.
An image encryption scheme based on the four-dimensional chaotic system and the mealy finite state machine
Authors: Zhang Xuncai , Liu Guanhe , Di Jiali
Published: March 2024

This paper proposes a four-dimensional hyperchaotic system to overcome the defect of weak encryption effect due to the simple complexity of low-dimensional chaotic systems in chaos-based image encryption schemes, which is verified to have better chaotic properties by dynamics analysis, sensitivity analysis, and randomness test. In addition, this paper proposes an image encryption scheme by combining the proposed chaotic system with the Mealy finite state machine (MFSM) to overcome the problem that some schemes are not resistant to statistical analysis. Firstly, the chaotic sequence is applied in the Knuth-Durstenfeld shuffling method to scramble the original image efficiently; secondly, according to the different information contained in the bit-plane, the pixel is decomposed and cyclically shifted at the bit level to achieve bit-level scrambling and diffusion; thirdly, the chaotic sequence is applied to select the rules for DNA encoding, and the diffusion process is achieved by Mealy finite state machine transformation; lastly, decoding the diffused image by selecting DNA rules randomly to get cipher image. This paper gives the experimental results, demonstrating that the scheme is highly secure. It can improve the encryption scheme’s sensitivity to plaintext and resist attacks such as differential attacks and select attacks.
The photon blockade in a three-wave mixing system coupled with a quantum dot
Authors: Mao Tong , Yao Zhihai , Yang Hui
Published: March 2024

In this paper, the photon blockade effect in a three-wave mixing coupling system with a quantum dot has been studied. By using analytical calculation and numerical analysis, we find that both the conventional photon blockade and the unconventional photon blockade effects could be realized in this system in strong-coupling regime just by one driving. Besides, compared with Jaynes–Cummings model, this hybrid system shows other obvious advantages in realizing the photon blockade, like blockading photon of more different frequencies, stronger antibunching effect. All the results may provide useful theoretical references for the single-photon devices design by using quantum dot and three-wave mixing system in future experiments and applications.
Study on ESIPT process of fluorescence probe BT-ITC for detecting H2S in DMF/H2O mixed solution
Authors: Ma Hongyu , Gu Ning
Published: March 2024

A probe molecule named BT-ITC with an isothiocyanate group was synthesized and evaluated for its H2S sensing ability based on the excited state intramolecular proton transfer (ESIPT) process J K Kim, S Y Bong, R Park, J Park, D Ok Jang 2022 An ESIPT-based fluorescent turn-on probe with isothiocyanate for detecting hydrogen sulfide in environmental and biological systems, Spectrochimica Acta Part A
278 121333. The BT-ITC molecule has a large Stokes shift, short response time, and low detection limit. The end result of the reaction between the molecules BT-ITC and H2S is the BTC-NH2 molecule. The hydrogen bond of the Enol structure BTC-NH2 molecule in excited-state (S1 state) is strengthened, compared to the ground-state (S0 state). The calculated absorption and fluorescence spectra were in good agreement with the experimental values. The frontier molecule orbitals (FMOs), the potential energy curve (PEC), and scatter plots of reduced density gradient (RDG) were calculated. According to aforementioned, it was discovered that the charges of BTC-NH2 molecule were rearranged via an electron transition brought on by photoexcitation. This changes the acidity and alkaline of the proton donor and acceptor, and thus promotes the ESIPT process.
Mathematical insights of social media addiction: fractal-fractional perspectives
Authors: Nadeem Anjam Yasir , Tabassum Saira , Arshad Muhammad , ur Rahman Mati , Ateeq Tahir Muhammad
Published: March 2024

The excessive use of social media has become a growing concern in the current century, with dependence on these platforms developing into a complex behavioral addiction. Addressing this issue requires the employment of well-directed and inclusive efforts. In pursuit of continuous development in existent strategies, this article presents a non-linear deterministic mathematical model that encapsulates the dynamics of social media addiction within a population. The proposed model incorporates the fractal-fractional order derivative in the sense of the Caputo operator. The objectives of this research are attained by groping the dynamics of the social media addiction model through the stratification of the population into five compartments: susceptible individuals, exposed individuals, addicted individuals, recovery individuals, and those who have quit using social media. The validity of the devised model is established by proving the existence and uniqueness of the solution within the framework of the fixed-point theory. The Ulam-Hyer’s stability is established through nonlinear functional analysis, perturbing the problem with a small factor. Utilizing the Adam Bashforth numerical scheme, we obtain numerical solutions, which we validate through MATLAB simulations. Additionally, we explore the application of artificial neural networks (ANNs) to approximate solutions, presenting a significant innovation in this domain. We propose the adoption of this novel method for solving integral equations that elucidate the dynamics of social media addiction, surpassing traditional numerical methods. Numerical results are illustrated across various fractional orders and fractal dimensions, with comparisons made against integer orders. Our study indicates that ANN outperforms the Adams-Bashforth algorithm, offering a dependable approach to problem-solving. Throughout the article, we underscore the competitive advantage of our proposed strategy, providing a more nuanced understanding of the complex dynamics outlined in the model.
Achievement of non-charge layer InGaAs/Si avalanche photodiodes by introducing a groove ring at the bonding interface
Authors: Ke Shaoying , Wang Jie , Huang Zhiwei , Li Jiahui , Zhou Jinrong , Liu Guanzhou
Published: March 2024

The avalanche photodiode (APD) is a prototypical example of a fast and high-gain detector, particularly in the infrared band, where it plays a crucial role in both military and civil optoelectronic devices. The combination of indium gallium arsenide (InGaAs) and silicon (Si) offers an ideal solution for achieving high-performance APDs. For traditional InGaAs/Si APDs, the incorporation of a p-Si charge modulation layer between InGaAs and Si is necessary for electric field modulation. This ensures that a high electric field is maintained in the multiplication layer while keeping it low in the absorption layer. However, the preparation of the p-Si charge modulation layer necessitates a tedious and expensive ion implantation process. Besides, the ion implantation process can also lead to material surface contamination that significantly affects the performance of the device. In this paper, an InGaAs/Si APD without the charge layer is reported. This approach is based on semiconductor direct bonding technology, wherein a groove ring is introduced into the bonding interface to replace the charge layer to regulate the electric field distribution. The electric field of the absorption layer and the multiplier layer is controlled by adjusting the number of grooved rings. By introducing 11 grooved rings into the bonding interface, we achieve a remarkable gain bandwidth product of 88.55 GHz. These findings hold significant implications for the future development of non-charge layer InGaAs/Si APDs with high-gain bandwidth products.
Taking into consideration a fifth-order nonlinear Schrödinger equation in an optical fiber
Authors: Wang Meng , Yang Yan-Fei , Chen Lan-Hua , Zhu Si-Ru
Published: March 2024

In this paper, symbolic computation on a fifth-order nonlinear Schrödinger equation is done, for the attosecond pulses propagation in an optical fiber. With respect to the complex amplitude of the optical pulse envelope, we work out a Lax pair and derive the modified generalized Darboux transformation. Then, we give the semirational solutions via the modified generalized Darboux transformation method. By means of such solutions, we graphically discuss the properties for three types of the degenerate solitons.
Chiro-plasmon responses of x-shaped titanium nitride (TiN) nanoarrays by numerical simulations
Authors: Zhang Xiao Yang , Du Chao Ling , Ding Yi Han , Xie Wei Wei , Lei Ming Xin , Zhang Xue Jin , Cao Shui Yan , Shi Da Ning
Published: March 2024

Titanium nitride (TiN) has recently been taken as a potential candidate for plasmonic material, which supports surface plasmon resonances and exhibits excellent thermal stability. In this article, we proposed a novel chiral metamaterial with TiN, which consists of X-shaped TiN nanorods periodically arranged on a glass substrate. Its extinction, circular dichroism (CD) spectra, and g-factors were calculated and regulated by the detailed geometry through numerical simulations using the finite element method to further boost the application of TiN in chiro-plasmonic system. We show that it presents chiral responses both in visible and near infrared (NIR) ranges. Under the optimized geometric parameters and NIR incidence, it predicts ∼4 and 2 fold E-field enhancement and g-factor, respectively, than that of experimental reports of TiN nanohelices. The obtained excellent chiro properties are elucidated well in terms of the obtained superchiral field and charge distributions, whose origin was analyzed by a linear superposition method. Moreover, the influence of dielectric environments is discussed as well. Overall, the findings underscore the potential of TiN as a chiro-plasmonic refractory metamaterial and shed light on the design of alternative chiro-plasmon metamaterials for NIR applications in the future.
Role of SiO2 in tailoring stability and nonlinear optical behaviour of gold nanoparticles in glass
Authors: Singla Shivani , Mahendru Nancy , Pandey Om Prakash , Chopra Neetu , Sharma Gopi
Published: March 2024

In the present work, a new approach is introduced to mitigate the loss of gold nanoparticles while preparing the glass through the traditional melt-quench technique. The role of refractory material i.e. SiO2 in loss reduction is studied by comparing the results obtained for bismuth borate (40Bi2O3:60B2O3) and borosilicate (40Bi2O3:40B2O3:20SiO2) glasses containing gold nanoparticles of different sizes (10 nm, 40 nm and 100 nm). The particle density and thermal stability obtained from FESEM and DTA, respectively, increase considerably with the presence of SiO2 as one of the components of glass composition. The nonlinear optical behaviour of both systems in non-resonant regions has been obtained using the Z-scan technique. In addition, the suitability of the prepared glasses for optical limiting and switching applications has been analysed.
Enhancing quantum metrology for multiple frequencies of oscillating magnetic fields by quantum control
Authors: Lei 雷 Xin 昕 , Fan 范 Jingyi 静怡 , Pang 庞 Shengshi 盛世
Published: March 2024

Quantum multi-parameter estimation has recently attracted increased attention due to its wide applications, with a primary goal of designing high-precision measurement schemes for unknown parameters. While existing research has predominantly concentrated on time-independent Hamiltonians, little has been known about quantum multi-parameter estimation for time-dependent Hamiltonians due to the complexity of quantum dynamics. This work bridges the gap by investigating the precision limit of multi-parameter quantum estimation for a qubit in an oscillating magnetic field model with multiple unknown frequencies. As the well-known quantum Cramér–Rao bound is generally unattainable due to the potential incompatibility between the optimal measurements for different parameters, we use the most informative bound instead which is always attainable and equivalent to the Holevo bound in the asymptotic limit. Moreover, we apply additional Hamiltonian to the system to engineer the dynamics of the qubit. By utilizing the quasi-Newton method, we explore the optimal schemes to attain the highest precision for the unknown frequencies of the magnetic field, including the simultaneous optimization of initial state preparation, the control Hamiltonian and the final measurement. The results indicate that the optimization can yield much higher precisions for the field frequencies than those without the optimizations. Finally, we study the robustness of the optimal control scheme with respect to the fluctuation of the interested frequencies, and the optimized scheme exhibits superior robustness to the scenario without any optimization.
Kinetic plasma-wall interaction using immersed boundary conditions
Authors: Munschy Yann , Bourne Emily , Dif-Pradalier Guilhem , Donnel Peter , Ghendrih Philippe , Grandgirard Virginie , Sarazin Yanick
Published: March 2024

The interaction between a plasma and a solid surface is studied in a (1D-1V) kinetic approach using immersed boundary conditions and penalization to model the wall. Two solutions for the penalized wall region are investigated that either allow currents to flow within the material boundary or not. Essential kinetic aspects of sheath physics are recovered in both cases and their parametric dependencies investigated. Importantly, we show how the two approaches can be reconciled when accounting for relevant kinetic effects. Non-Maxwellian features of the ion and electron distribution functions are essential to capture the value of the potential drop in the sheath. These features lead to a sheath heat transmission factor for ions 60% larger than usually predicted and 35% for electrons. The role of collisions is discussed and means of incorporating minimally-relevant kinetic sheath physics in the gyrokinetic framework are discussed.