Applied Physics A最新文献

{"title":"Tension–compression asymmetry of HCP CoCrFeMnNi high entropy alloy nanowires","authors":"Xuepeng Liu,&nbsp;Kaixin Xie","doi":"10.1007/s00339-025-08588-7","DOIUrl":"10.1007/s00339-025-08588-7","url":null,"abstract":"<div><p>The tension–compression asymmetry is commonly observed in conventional hexagonal close-packed (HCP) metals and its alloys, however, such a mechanical asymmetry still remains unclear in HCP high-entropy alloys (HEAs). In this study, we adopt molecular dynamics simulation to investigate the mechanical properties and deformation mechanisms of the HCP CoCrFeMnNi HEA nanowires under uniaxial tension and compression along the [0001] orientation. The results show that the HCP HEA nanowire exhibits an obvious tension–compression asymmetry at both the linear elastic and plastic deformation stages. Similar to the conventional HCP metals, the HCP CoCrFeMnNi HEA nanowire also shows elastic softening during tension while elastic hardening during compression. Such an elastic tension–compression asymmetry originates from the disparity in interatomic friction between the adjacent slip planes at the linear elastic regime under tensile and compressive loadings. In the plastic deformation stage, the yield and flow stresses of the HCP HEA nanowire in compression are both remarkably higher than the counterparts in tension, which can be ascribed to the completely different deformation mechanisms in tension and compression. Under the tensile loading, dislocation slip, phase transition, and deformation twinning are the dominant plastic deformation mechanisms and weakens the HCP HEA nanowire. During compression, dislocation slip and atomic amorphization dominates the plastic deformation and thus facilitates the strengthening. This work provides mechanistic insights into the deformation mechanism and mechanical response of the HCP HEAs, which is of importance for their rational design and device applications.</p></div>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":"131 6","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143932297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of non-stoichiometric ratios of the KI on the structure stability and optical properties of α-CsPbI3 perovskite thin films","authors":"Hadeer Mohamed Helal,&nbsp;Sameh I. Ahmed,&nbsp;Mohamed Bakr Mohamed,&nbsp;Ahmed Mourtada Elseman,&nbsp;Zein K. Heiba,&nbsp;Hassan Elshimy","doi":"10.1007/s00339-025-08563-2","DOIUrl":"10.1007/s00339-025-08563-2","url":null,"abstract":"<div><p>Inorganic CsPbI₃ perovskite has emerged as a promising light-absorbing material for photovoltaic applications, offering a suitable band gap for solar energy conversion and greater stability in ambient conditions compared to organic–inorganic halide perovskites. Nevertheless, the photoactive α-phase of CsPbI₃ remains stable only at higher temperatures, with a rapid phase transition to the inactive δ-phase occurring under room temperature conditions. Herein, we introduce a non-stoichiometric ratio of KI into CsPbI₃ film to stabilize the α-phase at room temperature. (XRD) analysis shows that the prepared CsPbI₃:<i>x</i>%KI, <i>x</i> = 0.0, 0.3, 0.5, 0.7, 1.0%, films exhibit the α-phase, notably, with 0.7% KI enhancing stability under ambient conditions. Also, scanning electron microscopy (SEM) showed that the optimal morphology was achieved with 0.7% KI. Grain size decreased with 0.7%KI then slightly increased with the addition of 1%, suggesting a suitable ratio for photovoltaic applications. Additionally, UV–Vis spectroscopy was employed to analyze the optical properties, demonstrating enhanced light absorption in the doped films. In the visible region, the absorption reduced sharply to its lowest value for the CsPbI₃:0.3%KI film and then increased as the KI ratio continued to rise. The optical energy gap (<i>E</i>_g) value of pristine CsPbI₃ film is 1.692 eV, which is reduced slightly and irregularly as the amount of KI doping increased, with the 0.5% KI-doped film attaining the lowest <i>E</i>_g value of 1.681 eV. Additionally, the photoluminescence (PL) spectroscopy showed higher intensity with 0.7%KI film, indicating fewer traps /defects and delayed recombination, improving the cell performance. These results suggest that KI doping significantly enhances the stability and optical properties of <i>CsPbI</i>_<i>3</i>, making it promising for perovskite solar cells.</p></div>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":"131 6","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143930147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"One-dimensional excitonic ground states in phosphorene atomic chains","authors":"Weidong Sheng","doi":"10.1007/s00339-025-08587-8","DOIUrl":"10.1007/s00339-025-08587-8","url":null,"abstract":"<div><p>One-dimensional phosphorene atomic chains are predicted to have excitonic ground states when an electric field is applied along the nanochain system. By using the configuration interaction approach beyond the conventional framework of independent multiexcitons, we reveal that the ground state of the atomic chain undergoes two successive transitions, first from purely electronic to excitonic and then to almost fully bi-excitonic with the increasing electric field. As the length of the nanochain increases, the transition fields at which the excitonic ground state emerges are found to gradually decrease and converge to 0.015 V/nm. Further analysis shows that clusters of high-lying states rapidly become localized around the left and right ends of the nanochain when the applied electric field increases. Such localization greatly enhances the correlations among the many-particle configurations, which are believed to result in firstly the excitonic then the bi-excitonic ground state being energetically more favorable.</p></div>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":"131 6","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143930149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reproducibility of 10 kV-class NiO/Ga2O3 heterojunction rectifiers","authors":"Jian-Sian Li,&nbsp;Chao-Ching Chiang,&nbsp;Hsiao-Hsuan Wan,&nbsp;Fan Ren,&nbsp;Stephen J. Pearton","doi":"10.1007/s00339-025-08527-6","DOIUrl":"10.1007/s00339-025-08527-6","url":null,"abstract":"<div><p>We summarize NiO/Ga₂O₃ vertical heterojunction rectifier results from two separate 2-inch diameter wafers with drift layer nominal thickness of 15 µm. For optimized edge termination dimensions, the breakdown voltages (V_B) in the regions of the wafers with the highest drift layer thickness (16.7–18.2 µm) and lowest background doping density (8 × 10¹⁵ cm⁻³) are consistently in the range 10-13 kV. Without edge termination, devices fabricated in the same areas show V_B of 8.3–8.8 kV. Over the entire wafer areas, the breakdown voltage can vary from 7.5-13 kV for the same optimized edge termination scheme. With a larger edge termination distance, the V_B is slightly improved. With a larger final metal extended distance, the V_B is significantly improved. With the radius of the final metal smaller than the extent of the NiO, the V_B is smaller or equal to the diodes without edge termination. There are two types of breakdown characteristic observed-in devices with abrupt increase in current near V_B, there is catastrophic breakdown at the edge of the final metal, whereas devices with gradual increases in current above 4–5 kV show no visible damage. The NiO/Ga₂O₃ rectifiers show negative coefficients of V_B of -12.9 V.K⁻¹, superior to that for Schottky barrier rectifiers fabricated on the same wafers, which exhibit values of -54.3 V.K⁻¹.</p></div>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":"131 6","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143925425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental optimization design for up-conversion luminescence properties and FIR based optical temperature sensing in BaGeTeO6: Er3+, Yb3+ fluorescent materials","authors":"Shengyi Liu,&nbsp;Duan Gao,&nbsp;Xin Chen,&nbsp;Li Wang,&nbsp;Wenbin Song,&nbsp;Han Yin,&nbsp;Ying Zhu,&nbsp;Shang Gao,&nbsp;Jingjing Zhang","doi":"10.1007/s00339-025-08542-7","DOIUrl":"10.1007/s00339-025-08542-7","url":null,"abstract":"<div><p>The regression equation correlating the doping concentration of Er³⁺/Yb³⁺ with luminescence intensity was established from a theoretical model, which was further refined through experimental optimization design. Then, the optimal solution of the equation was calculated by genetic algorithm, and the doping concentrations of Er³⁺ and Yb³⁺ were obtained to be 5.61 mol% and 33.55 mol% under 980 nm near-infrared radiation excitation, and 5.58 mol% and 28.88 mol% under 1550 nm near-infrared radiation excitation, respectively. Then, the Er³⁺/Yb³⁺ co-doped BaGeTeO₆ up-conversion phosphors powder was synthesized by high-temperature solid phase method. And the crystal structure of the resulting fluorescent powder was analysed by X-ray diffraction to confirm that the optimal BaGeTeO₆ samples were pure phase. The up-conversion fluorescence emission spectra of the samples were measured under 980 nm and 1550 nm pumping conditions, and strong green and red emissions were found with peaks at around 532 nm, 555 nm and 672 nm, corresponding to the jumps of the ²H_11/2→⁴I_15/2, ⁴S_3/2→⁴I_15/2 and ⁴F_9/2→⁴I_15/2 energy levels, respectively. For the optimal samples under these two pumping conditions, the relationship between the up-converted fluorescence and the laser operating current is explored.The up-converted fluorescence in these two cases is shown to be a two-photon and three-photon process, respectively, and the mechanism of the up-converted fluorescence is analysed and discussed in detail. In addition, the relationship between the up-conversion fluorescence and the temperature of the optimal samples is also investigated, revealing the excellent temperature sensing properties of the up-conversion emission under 980 nm and 1550 nm near-infrared radiation excitation.</p></div>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":"131 6","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143925427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Annealing temperature effects on the structural and magnetocaloric properties of La0.75Dy0.05Sr0.2MnO3","authors":"M. Baccari,&nbsp;A. Elghoul,&nbsp;A. Krichene,&nbsp;W. Boujelben,&nbsp;N. Chniba Boudjada","doi":"10.1007/s00339-025-08567-y","DOIUrl":"10.1007/s00339-025-08567-y","url":null,"abstract":"<div><p>The search for efficient magnetic refrigerants near room temperature is still motivating the scientific committee. In this context, we have tried to study the effect of annealing temperature on the structural, magnetic and magnetocaloric properties of the La_0.75Dy_0.05Sr_0.2MnO₃ compound, synthesized by the sol–gel method. The structural analysis revealed the coexistence of both rhombohedral <i>R</i> <span>(overline{3 })</span> <i>c</i> and orthorhombic <i>Pnma</i> structural phases, with the presence of some impurities for the nanosized compound sintered at 800 °C. All the samples display a ferromagnetic–paramagnetic transition, with the presence of a glassy state at low temperatures. Reducing the sintering temperature from 1200 °C to 1000 °C shifts the Curie point to higher temperatures, which can be linked to the weakening of superexchange interactions. The results of the magnetocaloric study show that the compound sintered at 1000 °C exhibits an important relative cooling power (80.05 J.kg⁻¹) under a magnetic field of 2 T at 285 K, which suggests that this compound is a potential candidate for magnetic cooling near room temperature.</p></div>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":"131 6","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143925443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical analysis of 40 kW multistack fuel cell system featuring series-type active hydrogen recovery","authors":"Jenn-Kun Kuo,&nbsp;Satya Sekhar Bhogilla,&nbsp;Tzu-Hsiang Lin,&nbsp;Yi-Hung Liu,&nbsp;Jiří Ryšavý,&nbsp;Jakub Čespiva","doi":"10.1007/s00339-025-08554-3","DOIUrl":"10.1007/s00339-025-08554-3","url":null,"abstract":"<div><p>MATLAB/Simulink simulations are performed to investigate and innovative the performance of a multistack fuel cell (MFC) system consisting of 1 ~ 4 10 kW fuel cells arranged in a series configuration. The system is equipped with a tail purge valve, fixed to vent impurities from the stack every 60 s, and an active hydrogen recovery system based on a mechanical compressor to recover the excess hydrogen from the exhaust stream and return it to the inlet side for re-use. The validity of the simulation model is confirmed by comparing the rated power output of the MFC system with that of a commercial fuel cell platform. The validated model is employed to evaluate the I-V response of the 10 kW, 20 kW, 30 kW and 40 kW MFC systems. The effects of the stack temperature on the output power are then investigated. It is shown that, for each MFC system, the maximum efficiency is obtained for stack temperatures in the range of 65–75 °C. Moreover, the system efficiency increases by approximately 7% as the cathode air pressure increases from 1.1 bar to 1.8 bar. Finally, the active hydrogen recovery ratios of the 20 kW, 30 kW and 40 kW MFC systems are found to be 14.1%, 11.8%, and 10.65%, respectively.</p></div>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":"131 6","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143925426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental investigations into the effect of low temperature empowerment on the grooves quality of ITO conductive glass using by micro grinding","authors":"Xi Chu,&nbsp;Yin Liu,&nbsp;Xingwei Sun,&nbsp;Yuxuan Lu,&nbsp;Haosheng Dong,&nbsp;Fei Pan,&nbsp;Wei Xu,&nbsp;Zewei Yuan,&nbsp;Shibo Mu,&nbsp;Sheng Qu","doi":"10.1007/s00339-025-08570-3","DOIUrl":"10.1007/s00339-025-08570-3","url":null,"abstract":"<div><p>This paper conducted a single-factor experiments of micro-scale grinding of ITO conductive glass, changing the feed speed, grinding depth and spindle speed. The effects of temperature reduction on the micromorphology, surface roughness and transmittance of the machined surface were analyzed by comparing the experiments at normal temperature. The results show that different areas of the groove present different morphologies, and there are obvious scratch areas on the side walls of the groove. The removal mode of the glass substrate is mainly the evolution and interweaving of the initial micro-damage. The micro-morphology is mainly pits and cracks of different sizes. The indium tin oxide film is mostly flaky and curled. The reduction of processing temperature improves the hardness and strength of the material, inhibits the further evolution of damage when the processing parameters change, and improves the surface quality. Low-temperature grinding produces more powder chips with smaller size. The appropriate amount of chip accumulation can improve the processing quality and tool wear. The transmittance of light of different wavelengths is sensitive to temperature changes to different degrees. The transmittance of ultraviolet and visible light of the workpiece is improved after low-temperature processing. The research reveals the low-temperature grinding characteristics of ITO conductive glass based on experiments, which is helpful to optimize the design and implementation of low-temperature grinding process, and proves that it is a feasible way to improve the processing quality of ITO conductive glass by mainly removing brittleness.</p></div>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":"131 6","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143925444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficient perovskite solar cells with tunable transmittance using transparent conductive silver nanowire network electrodes","authors":"Xinlei Wang,&nbsp;Bingqiang Cao","doi":"10.1007/s00339-025-08566-z","DOIUrl":"10.1007/s00339-025-08566-z","url":null,"abstract":"<div><p>Semi-transparent perovskite solar cells (ST-PSCs) have garnered significant attention in the field of building-integrated photovoltaics (BIPV). However, a balance between device transmittance and efficiency is crucial for practical applications. In this study, we employed a full solution process to fabricate low-cost, high-efficiency transparent perovskite solar cells (PSCs) with tunable transmittance. By adjusting the concentrations of the perovskite precursors, we produced perovskite films of varying thicknesses. These films were then combined with silver nanowire (Ag NWs) electrodes, which offer high transmittance and conductivity, to create PSCs with adjustable transmittance. Among the applied concentrations, the 1.2 mol/L precursor solution based devices yielded the highest photovoltaic conversion efficiency of 17.3%, with an average visible light transmittance (AVT) of 5.3%. Conversely, with the 0.8 mol/L precursor solution, we achieved an efficiency of 13.4% at an AVT of 16.8%. These findings address the challenges of energy consumption and cost, as well as the trade-off between efficiency and average light transmittance, in ST-PSCs for potential BIPV applications.</p></div>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":"131 6","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143925441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The structural, morphological, and magnetic properties of MnxNi1-xO/NiO thin film bilayers","authors":"Md Ashif Anwar,&nbsp;Robert A. Mayanovic","doi":"10.1007/s00339-025-08507-w","DOIUrl":"10.1007/s00339-025-08507-w","url":null,"abstract":"<div><p>The exchange bias (EB) effect, especially in nanomaterials, is highly promising for use in antiferromagnet-based spintronics applications. NiO is a well-known antiferromagnetic material with a high Néel temperature (525 K) that can exhibit ferromagnetism/ferrimagnetism by addition of other magnetic transition elements. Our previous work has shown that the antiferromagnetic (AFM) characteristics of conventional NiO nanostructured material can be altered to have substantial ferrimagnetic (FiM) characteristics by doping with Mn or Co. Pulsed laser deposition (PLD) was used to grow heterostructures comprised of a nanostructured thin NiO film deposited on the surface of MgO (100) and Al₂O₃ (0001) substrates, followed by the deposition of a Mn_xNi_1−xO thin film layer on top of a NiO layer. X-ray diffraction (XRD), scanning electron microscopy (SEM), and physical property measurement system (PPMS) magnetometry were used to study the structural, morphological, and magnetic properties, respectively, of the thin film heterostructures. XRD and SEM characterization show that the Mn_xNi_1−xO/NiO bilayers were grown quasi-epitaxially on the MgO (100) and Al₂O₃ (0001) substrates. Although both heterostructures were found to be crystalline with nominal disorder characteristics, the Mn_xNi_1−xO/NiO/Al₂O₃(0001) thin film heterostructure was found to have more extensive crystallinity. The Mn_xNi_1−xO/NiO thin film bilayer exhibits FiM/AFM interface characteristics at 5 K, including the exchange bias effect, regardless of the nature of the substrate that the films were grown on. However, only the Mn_xNi_1−xO/NiO thin film bilayer grown on the Al₂O₃ (0001) substrate was found to have a persistent exchange bias field at room temperature.</p></div>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":"131 6","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143925523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}