The European Physical Journal B最新文献

In this paper, a metasurface structure with dual-layer structure was designed. Two vertical metal bars and three U-shaped metal patterns are prepared on substrate of printed circuit board (PCB). By analyzing the transmission comparison with partial of the structure, it was analyzed that the reason for the multiband analogous electromagnetically induced transparency (EIT) of the structure is obtained by multimode coupling, and the resonance mechanism of the structure was analyzed by multipole scattering theory. By analyzing the electric field distribution of the structure, the physical mechanism of analogous EIT generation of the structure is obtained. The influence of the structure parameters on analogous EIT phenomena is further analyzed. By comparing the measured results with the calculated results in a microwave anechoic chamber, the results are in good agreement. The structure has potential applications in multiband filter, refractive index sensor, and microwave devices.

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The rhombohedral La_0.8K_0.175Li_0.025MnO₃ sample was elaborated using the sol–gel method at low temperature of 900 °C. The prepared sample exhibits a second-order paramagnetic-ferromagnetic transition with decreasing temperature. Based on the data of the magnetic measurements, the critical behavior analysis is investigated through various techniques such as modified Arrott plot, Kouvel–Fisher method and critical isotherm analysis. The critical exponents determined using the Kouvel-Fisher method are found to be (beta ) = 0.533 and (gamma ) = 1.114 at ({T}_{C}) ~ 270 K. The critical exponent values obtained are in agreement with the values predicted by the mean field model, indicating the existence of long-range magnetic interaction in our synthesized sample. The maximum of the magnetic entropy change is about 3.51 J kg⁻¹ K⁻¹ under a magnetic applied field change of 5 T. The relative cooling power is found to be 320.5 J kg⁻¹ at 5 T. This value represents about 78% of that of standard gadolinium.

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This issue contains peer-reviewed papers based on selected contributions presented at the International Conference on Statistical Physics (SigmaPhi) held in Chania-Crete (Greece) from July 10th to July 14th, 2023 (http://sigmaphisrv.polito.it/). The challenge facing statistical physics today is expanding beyond conventional conceptions of physics, bringing together multiple research streams that were thought to be separate and independent for the majority of the 20th century. In this topical issue, we present a collection of papers that demonstrate the current applications of statistical physics in a variety of different fields, including networks, biophysics, statistical mechanics, kinetic theory, and cosmology.

In recent era, there has been a boosting inclination towards the investigation of Heusler materials, owing to their extensive applications in thermoelectronics and optospintronics. The structural, elastic, electronic, magnetic and thermoelectric properties of RuCrM (M = Si, Ge, Sn, Sb) half-Heuslers are systematically studied by using the DFT and DFT + U methods. The calculated results of lattice constant and bulk modulus are in good agreement with the existing theoretical data for similar RuCrM systems. The magnetic and electronic properties reveal that RuCrM are FM metallic materials. In addition, the two types of doping by electrons and holes at various temperatures are investigated for RuCrM, and their optimum structural type is estimated. This study concludes that the U energy has the potential to enhance the properties of RuCrM. Such remarkable properties provide strong evidence that the stable compounds of RuCrM are suitable and promising materials for future thermoelectronics and optospintronics applications.

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In this study, a mathematical model is developed to study the transport properties of a system consisting of serially coupled double-quantum dots embedded between two nonmagnetic leads in the presence of a laser field effect on double-quantum dots. To examine the device properties and develop a spin-dependent analytical formula for the occupancy numbers, related quantum dot energy levels and the molecular virtual levels, the treatment in this research is based on the time-independent Anderson–Newns model. These formulas are solved self-consistently to compute the tunneling current which is utilized to calculate the differential conductance “Our calculations focus on the strong regime”. All the parameters that included in our calculations can be tuned experimentally. It is found that the electron transport through the system is enhanced as the frequency of the laser field increases, and the energy window is getting wider too. These results are very important to be applied to nano-devices, since the laser can be used as a tool to assist the transport of electrons through the system.

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Cerium dioxide (CeO₂) or Ceria nanorods were produced in the current work, using the chemical precipitation approach. X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), UV–visible, photoluminescence (PL), and electrochemical impedance spectroscopy (EIS), thermogravimetric and differential thermal analyses (TG/DTA) were used to assess the material characteristics of the produced samples. The XRD results reveal that the CeO₂ nanorods crystallized into the cubic fluorite crystal system. Micro-strain dislocation density, gain size and cell volume of the samples were assessed. XPS examination was performed to verify the chemical states of the constituent elements in CeO₂ nanorods. FTIR spectral analysis was used to investigate chemical bonds and molecular vibrations in CeO₂ nanorods. SEM analysis was used to observe the grain structure of CeO₂ nanorods. UV–visible spectroscopy determined the CeO₂ optical absorption characteristics, bandgap, and Urbach energy. PL study and CIE-chromaticity mapping were used to investigate the light-emitting characteristics of the CeO₂ nanorods. The EIS method was applied to examine the impedance nature of CeO₂ nanorods. TGA/DTA investigations were performed to find the thermal characteristics of CeO₂ nanorods. The study findings indicate the usefulness of CeO₂ nanorods as electrodes and optoelectronic materials.

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