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In this study, we investigate the anomalous magnetic moment of the muon (g μ − 2) as reported by Fermilab (FNAL), along with the recent measurement of the W -boson mass by the CDF-II collaboration. Both findings show significant deviations from the predictions of the Standard Model (SM), hinting at the possibility of new physics. Our focus is on the Type III two-Higgs-doublet model (2HDM), wherein both Higgs doublets couple with all fermions, leading to the induction of flavour-changing neutral currents (FCNCs) at the tree level. Within this framework, we investigate a lepton-flavour-violating (LFV) scenario, aiming to explain both observed anomalies, while satisfying the up-to-date theoretical and experimental constraints. [ABSTRACT FROM AUTHOR]

In the absence and presence of a circularly polarized monochromatic electromagnetic pulse, we have analyzed the electron–nucleon scattering process, where the nucleon is assumed to be spinless with a spherical shape. We have provided the theoretical calculation of the differential cross section (DCS) by using the Dirac–Volkov formalism. This research paper aims to provide two comparisons: We first compare the DCS in the absence of the laser field with its corresponding laser-assisted DCS. A second comparison is made between the electron–proton and electron–neutron scattering processes to study the effect of the laser on both processes. The results obtained about the effect of the laser field on the DCS and the electric form factor have been discussed for both scattering processes. We have found that the DCS is reduced when the laser field is applied for both processes. In addition, the form factor is also decreased by raising the incident electron energy in electron–proton scattering, but it increases in electron–neutron scattering. Moreover, the form factors for both scattering situations are unchanged by raising the laser field strength up to 1 0 8 V/cm. [ABSTRACT FROM AUTHOR]

This study employs a first-principles approach to comprehensively examine the structural, electronic, optical, and magnetic properties of the thermodynamically stable scintillating double perovskite halides A 2 N a T a X 6 ( A = C s , R b ; X = C l , B r , I ). The dynamic stability of these materials were explained based on deduced phonon properties. Our analysis reveals that these compounds exhibit intriguing electronic behavior with spin polarization, demonstrating half-metallicity. In spin-up, the band gap is found to be zero, while in spin-down, it falls within the range of 3 to 4 eV with the incorporation of DFT+U corrections. Notably, the optical properties assessment highlights the exceptional UV and high-energy absorption capabilities of A 2 N a T a I 6 , making it a promising candidate for scintillation applications in particle detection. This research sheds light on the unique and versatile properties of these materials, with implications for various technological and scientific applications. [ABSTRACT FROM AUTHOR]

This research work investigates the structural, electronic, optical, and thermoelectric characteristics of VFeZ (Z = N and P) half‐Heusler compounds. The study employs the full‐potential linearized augmented plane wave (FP‐LAPW) method integrated into the WIEN2K algorithm, serving as the underpinning framework for density functional theory (DFT) analysis. In the study, we use the PBE generalized gradient approximation (PBE‐GGA) to identify numerous parameters associated with structural and elastic properties. Lattice parameter results are in agreement with previous outcomes. Moreover, computed elastic parameters satisfy the criterion for stability. In the cubic structure VFeZ (Z = N and P) is ductile, to enhance the computations of electronic characteristics, Tran and Blaha's modified Becke‐Johnson potential (TB‐mBJ) is used. Our simulations demonstrate that the materials exhibit semiconductor behavior, with a direct band gap for VFeZ (Z = N and P). Strong UV absorption is found via optical experiments suggest compounds are suitable for optical application. Furthermore, study of the thermoelectric properties suggests its application in the thermoelectric generators. [ABSTRACT FROM AUTHOR]

The two-body leptonic decays of both light and heavy-charged mesons X l 2 ± are investigated in the first Born approximation in the presence of a monochromatic and circularly polarized laser field. As a result of using Volkov functions, the analytic study of these processes has brought a change in the parameters associated with each decay process. The decay width, lifetime, and branching ratio of each decay process are affected by increasing the classical parameter ξ of the meson. A comparison between the matter decay X l 2 + and that of the anti-matter X l 2 - in the presence of a circularly polarized laser wave, indicates that increasing laser field strength (increasing the classical parameter ξ ) can induce a slight dominance of matter over antimatter or vise versa. [ABSTRACT FROM AUTHOR]

The Full Potential Linearised Augmented Plane Wave method (FP-LAPW) is used to design the structural, elastic-mechanical, electronic, magnetic, and thermoelectric prop-erties of new cubic double perovskite oxides X 2 C e V O 6 (X = S r , B a) . The tolerance factor and elastic parameters show and ensure the stability and formation of both perovskites in the cubic phase. Additionally, the predicted mechanical constants show that X 2 C e V O 6 (X = S r , B a) behave as stable ductile materials. Then, spin-polarized calculations show ferromagnetic and half-metallic behavior for both compounds with a total magnetic moment equal to 1 μ β . Thermoelectric parameters of both materials show high power factor and n-type conductivity, due to the multiple oxidation states of Vanadium. Therefore, these results show that the proposed perovskites X 2 C e V O 6 (X = S r , B a) can be promising materials for spintronic and thermoelectric applications. [ABSTRACT FROM AUTHOR]

In a previous paper, we showed theoretically that the total cross-section of the top-quark pair production by electron–positron annihilation is strongly reduced by the presence of a circularly polarized laser field. In this paper, we present the result for the case of a linearly polarized laser field. This time, the total cross-section is significantly enhanced by the laser field. [ABSTRACT FROM AUTHOR]

In this study, we investigate the halide perovskite material Cs 2 LiLuCl 6 using both density functional theory (DFT) and time-dependent density functional theory (TD-DFT) approaches. Our analysis focuses on the structural, electronic, and optical properties of the material, conducted with the Quantum Espresso code. In order to confirm the structural stability of the material, we performed various tests including analysis of elastic constants, formation energy, tolerance factor, and phonon dispersion. Employing the generalized gradient approximation (GGA) and GGA+U, we determine that the material behaves as an insulator with a direct band gap of 5.3042 eV and 5.4245 eV, respectively. Additionally, DFT+U calculations were performed to study the dielectric function, reflectivity, absorption coefficient, and refractive index, revealing a high transmittance rate exceeding 90%. Under ideal conditions, the upper light yield (LYsc) is estimated to be 75 411 ph/MeV and 73 739 ph/MeV for the DFT and DFT+U methods, respectively. These results, along with the presence of lithium in Cs 2 LiLuCl 6 , highlight its potential for use in scintillation-based thermal-neutron detection applications. • Cs2LiLuCl6 is stable in a cubic structure as shown by its formation energy and phonon data. • Cs2LiLuCl6 exhibits insulating behavior with a direct band gap. • The material has high UV emissivity, improving scintillation applications. • Cs2LiLuCl6 achieves 75,411 photons/MeV (DFT) and 73,739 photons/MeV (DFT+U). [ABSTRACT FROM AUTHOR]

Recent advancements and developments in photovoltaic materials have made significant progress owing to the search for efficient and sustainable energy sources. Although lead halide perovskites have demonstrated impressive performance in solar cell applications, they face challenges such as environmental instability and lead toxicity. This study investigates several physical properties of two lead-free double halide perovskites, Rb2CuAsBr6\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$Rb_{2}CuAsBr_{6}$$\end{document} and Rb2TlAsBr6\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$Rb_{2}TlAsBr_{6}$$\end{document}, and evaluates their potential for solar cell applications using density functional theory (DFT) within the Wien2k code and spectroscopic limited maximum efficiency (SLME) approach. The negative formation energy and Born criteria confirm the structural stability of both perovskites in the ideal cubic structure. Optoelectronic analyses reveal that Rb2TlAsBr6\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$Rb_{2}TlAsBr_{6}$$\end{document}, with a direct band gap of 1.51 eV, exhibits better photovoltaic characteristics compared to Rb2CuAsBr6\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$Rb_{2}CuAsBr_{6}$$\end{document}, which has an indirect band gap of 0.60 eV. Additionally, the SLME analysis shows that Rb2TlAsBr6\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$Rb_{2}TlAsBr_{6}$$\end{document} achieves a higher SLME of approximately 31.4 %, compared to Rb2CuAsBr6\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$Rb_{2}CuAsBr_{6}$$\end{document} which has a SLME of 7.44%. Moreover, the calculated thermoelectric properties show that Rb2TlAsBr6\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$Rb_{2}TlAsBr_{6}$$\end{document} exhibits enhanced thermoelectric performance compared to Rb2CuAsBr6\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$Rb_{2}CuAsBr_{6}$$\end{document}. These findings highlight the potential of lead-free perovskites, particularly Rb2TlAsBr6\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$Rb_{2}TlAsBr_{6}$$\end{document}, for next-generation solar cell applications. [ABSTRACT FROM AUTHOR]

Owing to their proper characteristic, simple halide perovskites became engaged over time for thermoelectric applications. In this work, several physical properties of simple halide perovskite materials AInBr 3 (A = K, Rb) are predicted based on density functional theory (DFT) within the Wien2k code. The tolerance factor and negative formation energy demonstrate the stability and formation of these compounds, and the Born criteria shows their mechanical stability and inherent ductility. Notably, the modified Becke-Johnson potential (mBJ) was used to calculate the optoelectronic characteristics. The AInBr 3 (A = K, Rb) perovskites present semiconducting aspects. Analyses of their optical characteristics, including refractive index, reflectivity, were performed. AInBr 3 (A = K, Rb) transport properties were studied. The highest figure of merit was attained by AInBr 3 (A = K, Rb) which had a high Seebeck coefficient and high electrical conductivity. Finally, all studied properties of simple halide perovskites give a new way for efficient applications in thermoelectric. • The structural, electrical, optical, and thermoelectric properties of cubic perovskite AInBr 3 (A = Rb, K) are demonstrated. • The compounds are suitable for optoelectronic applications since their maximal absorption occurs in the visible spectrum. • The high-power factor and figure of merit of AInBr 3 (A = Rb, K) indicate that the examined compounds are appropriate for thermoelectric applications. [ABSTRACT FROM AUTHOR]