Current Applied Physics最新文献

{"title":"Thermal annealing induced multifold enhancement in thermoelectric power factor of β-Zn4Sb3 thin films","authors":"Avinash Kumar ,&nbsp;Nirmal Manyani ,&nbsp;Janpreet Singh ,&nbsp;S.K. Tripathi","doi":"10.1016/j.cap.2025.09.014","DOIUrl":"10.1016/j.cap.2025.09.014","url":null,"abstract":"<div><div>In the present work, thermoelectric parameters electrical conductivity, Seebeck coefficient and power factor of β-Zn₄Sb₃ thin films at room temperature (303 K) were enhanced by 102.56 %, 110.90 % and 712.76 % respectively using post-deposition thermal annealing approach. Multiphase Rietveld refinement analysis was implemented to determine phase quantification, lattice parameters, atomic positions and occupancies, bond lengths &amp; angles and crystal structure of the synthesized material. Maximum electrical conductivity, Seebeck coefficient and power factor values of <span><math><mrow><mn>1.58</mn><mo>×</mo><msup><mn>10</mn><mn>4</mn></msup><mspace></mspace><mi>S</mi><msup><mi>m</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math></span>, 232 <span><math><mrow><mi>μ</mi><mi>V</mi><msup><mi>K</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math></span> and 764 <span><math><mrow><mi>μ</mi><mi>W</mi><msup><mi>m</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup><msup><mi>K</mi><mrow><mo>−</mo><mn>2</mn></mrow></msup></mrow></math></span> at 303 K were obtained after annealing of thermally evaporated β-Zn₄Sb₃ thin films for 6 h. Enhancement in electrical conductivity values were attributed to lowered band gap values, reduced defects &amp; grain boundaries, large crystallite sizes and reorientation of growth direction caused by annealing. Enhancement in Seebeck coefficient values were attributed to the energy filtering effects promoted by increasing surface roughness. Structural characteristics of thin films were investigated, revealing reorientation of crystallites growth direction via thermal annealing. Investigation of optical characteristics revealed a band gap energy value of 1.28 eV for without annealed β-Zn₄Sb₃ thin film. Morphological properties of thin film surfaces revealed aggregation of grains due to annealing at elevated temperatures and average thin film thickness of 323 nm was determined. Topographical characteristics of thin films were investigated to visualize 3D surface maps, line profile and determine surface roughness.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":"80 ","pages":"Pages 311-326"},"PeriodicalIF":3.1,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145262493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bipolar resistive switching characteristics of silver doped tin sulphide based ReRAM devices","authors":"Neju Mathew Philip,&nbsp;M.C. Santhosh Kumar","doi":"10.1016/j.cap.2025.08.013","DOIUrl":"10.1016/j.cap.2025.08.013","url":null,"abstract":"<div><div>In the present work, silver doped tin sulphide (SnS:Ag) thin films are deposited using the vacuum thermal evaporation over stainless steel (SS 304) substrates. X-ray diffraction studies and Raman analysis confirmed the formation of orthorhombic SnS without any impurity phases. FE-SEM analysis revealed a coral reef-like morphology for the deposited SnS:Ag thin films. EDS studies revealed tin-rich SnS:Ag thin films. The resistive memory switching characteristics of the fabricated SS/SnS:Ag/Ag ReRAM device is analysed and the On/Off ratio of the device is obtained as 40.7. The SS/SnS:Ag/Ag device has good endurance over 100 cycles and retention over 10⁴ s. The creation and dissolution of conductive filaments of silver and sulphur ions through the tin vacancies is the possible conduction mechanism behind the memory switching property of the fabricated SS/SnS:Ag/Ag memory device.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":"80 ","pages":"Pages 37-42"},"PeriodicalIF":3.1,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144921988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance evaluation of flux reversal machines with rare-earth and non-rare earth excitations for micro wind energy","authors":"Manne Bharathi ,&nbsp;Obbu Chandra Sekhar ,&nbsp;Suresh Lakhimsetty","doi":"10.1016/j.cap.2025.09.002","DOIUrl":"10.1016/j.cap.2025.09.002","url":null,"abstract":"<div><div>Cogging torque in flux-reversal machines (FRM) is relatively high compared with other types of stator active PM machines, due to their unique double salient topology. This research develops a hybrid novel skew with rotor pole pairing (SKCpp) method and analyses it using 2D finite element analysis (FEA), comparing its performance with two distinct excitation topologies, i.e., rare earth (RE-FRM) and ferrite (NRE) flux reversal machines (FRMs). The 3-phase, 6/8 pole FRM is modeled, and electromagnetic performances are compared with RE excited FRM (Machine A) and NRE excited FRM (Machine B), which have similar performance requirements for wind generator applications. These various excited machines are evaluated based on their power generation performance, demonstrating exceptional overload and speed capabilities through 2D FEA. The efficiency of Machine A is somewhat higher than that of Machine B, but cogging torque and torque ripples are at least 40 % higher than those of the former. It is found that the torque density of Machine B is only 54 % of that of Machine A, but by employing this structure, the cost saving is achieved by 47 %, since the machine is 1.8 times heavier. Further, the demagnetization risk analysis is performed up to 150 °C. At higher temperatures, Machine A is prone to deeper demagnetization risk, due to temperature susceptibility, which degrades the power factor and thereby limits the performance of the generator. Unlike Machine A and Machine B, which possess the minimum demagnetization risk, the occurrence is recorded below room temperature. Overall summary, it is found that the NRE excited proposed Machine B is the best alternative to the RE excited proposed Machine A for medium speed wind turbine generator applications.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":"80 ","pages":"Pages 51-63"},"PeriodicalIF":3.1,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145019359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental study of the nonlinear optical properties of Na2SO4 single crystal","authors":"M.Ya. Rudysh ,&nbsp;J. Jędryka ,&nbsp;G.L. Myronchuk ,&nbsp;V.M. Kordan ,&nbsp;R.V. Gamernyk ,&nbsp;R.S. Brezvin ,&nbsp;А.І. Kashuba ,&nbsp;M.I. Shevchuk","doi":"10.1016/j.cap.2025.10.008","DOIUrl":"10.1016/j.cap.2025.10.008","url":null,"abstract":"<div><div>In the work, a single crystal of Na₂SO₄ of good optical quality was obtained. Its structure was verified and crystallographic parameters were refined. The infrared transmission spectra were studied and it was shown that it is transparent in a wide spectral range. The second harmonic generation of powder samples of the Na₂SO₄ crystal at the fundamental wavelength of 1064 nm was studied. An increase in the efficiency of the second harmonic generation with an increase in the power of the fundamental beam was established. The efficiency of the SHG is greater than that for the previously studied LiNH₄SO₄ crystal in the β-modification. The nonlinear optical refraction of the Na₂SO₄ crystal under the action of a laser beam λ = 532 nm was studied. The crystal is characterized by optical self-defocusing (<em>n</em>₂ &lt; 0) and the value of the obtained nonlinear optical refractive index is <em>n</em>₂ = −3.89 × 10⁻¹³ m²/W.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":"80 ","pages":"Pages 376-382"},"PeriodicalIF":3.1,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145424833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Landau-Devonshire theory-based phase diagram of the bismuth ferrite and barium titanate solid solution","authors":"Hae In Choi ,&nbsp;Myang Hwan Lee ,&nbsp;Won-Jeong Kim ,&nbsp;Tae Kwon Song","doi":"10.1016/j.cap.2025.10.009","DOIUrl":"10.1016/j.cap.2025.10.009","url":null,"abstract":"<div><div>The development of high-performance, lead-free piezoelectric ceramics is essential for modern sensor and actuator applications. Bismuth ferrite-based solid solutions, like (1-<em>x</em>)BiFeO₃-<em>x</em>BaTiO₃ (BF-BT), are promising due to their high Curie temperature and high piezoelectric performance, but ambiguities persist regarding their phase transitions and the exact location of the morphotropic phase boundary (MPB), where piezoelectric properties are maximized. This study resolves these issues by applying Landau-Devonshire theory to construct a comprehensive phase diagram for the BF-BT system. By calculating the free energy density landscape, our theoretical model accurately reproduces the material's composition-dependent properties. The resulting phase diagram agrees well with experimental observations, predicting a coexistence of rhombohedral and tetragonal phases near <em>x</em> = 0.33. And our calculations identify the MPB at a composition of <em>x</em> = 0.375, consistent with the experimentally reported range. These findings highlight the link between phase structure and piezoelectric performance.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":"80 ","pages":"Pages 362-366"},"PeriodicalIF":3.1,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145358202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optical and structural properties of indium oxide prepared by spray pyrolysis as a NO2 and H2S gas sensor","authors":"Haidar K. Dhayef ,&nbsp;Nisreen Ahmed Hamzah","doi":"10.1016/j.cap.2025.09.006","DOIUrl":"10.1016/j.cap.2025.09.006","url":null,"abstract":"<div><div>Spray pyrolysis was employed to synthesize indium oxide nanostructures. The material was characterized using energy-dispersive X-ray spectroscopy (EDX), field emission scanning electron microscopy (FESEM), and X-ray diffraction (XRD). Thin films of indium oxide (In₂O₃) were produced by spray pyrolysis for gas sensing applications. The films were analyzed by XRD, FESEM, EDX, and UV–Vis spectroscopy. XRD analysis revealed a cubic polycrystalline structure with crystallite sizes ranging from 12 to 17 nm, while FESEM showed grass-like nanostructures with diameters between 40 and 70 nm. UV–Vis spectroscopy indicated an optical band gap of ∼3.27 eV. The gas sensor exhibited very high sensitivity to NO₂ and H₂S gases, with maximum sensitivities of 69.9 % and 32.25 %, respectively, at 300 °C. The device also demonstrated rapid response and recovery times, making it an ideal candidate for environmental gas detection.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":"80 ","pages":"Pages 122-127"},"PeriodicalIF":3.1,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145060032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electrical transport and thermopower of reduced Ruddlesden-Popper phase Srn+1TinO3n+1-δ (n = 1, 2, 3, ∞) thin films","authors":"Zhen Yang ,&nbsp;Bingxu Liu ,&nbsp;Zhuangzhi Li ,&nbsp;Xi Han ,&nbsp;Zilin Ye ,&nbsp;Cici Jin","doi":"10.1016/j.cap.2025.09.009","DOIUrl":"10.1016/j.cap.2025.09.009","url":null,"abstract":"<div><div>High quality Ruddlesden-Popper phase Sr_<em>n</em>+1Ti_<em>n</em>O_{3<em>n</em>+1} (<em>n</em> = 1, 2, 3, ∞) thin films were epitaxially grown on LaAlO₃ (001) single crystal substrates using pulsed laser deposition and then reduced in a gas mixture of H₂ and Ar at 1473 K. Their conductivities and Seebeck coefficients were investigated by focusing on various transport mechanisms. At low temperatures, the conductivity results show that electron-electron interactions dominate electrical transport. At room temperature, both conductivity and Seebeck coefficient results indicate that conduction follows the small polaron model. At 300 K, the power factors for SrTiO_{3-<em>δ</em>}, Sr₄Ti₃O_{10-<em>δ</em>} and Sr₃Ti₂O_{7-<em>δ</em>} reduced thin films reach 0.016, 0.017, and 0.006 mW/m⋅K², respectively.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":"80 ","pages":"Pages 128-133"},"PeriodicalIF":3.1,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145105113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phase change materials and building envelope: An innovative solution for energy transition","authors":"S. Jellaj ,&nbsp;S. Ouhaibi ,&nbsp;L. Zahiri ,&nbsp;N. Belouaggadia","doi":"10.1016/j.cap.2025.09.003","DOIUrl":"10.1016/j.cap.2025.09.003","url":null,"abstract":"<div><div>The energy efficiency of buildings is a critical challenge in regions with harsh climates, where heating and cooling demands are steadily increasing. Among the most promising passive strategies, the integration of phase-change materials (PCMs) into building envelopes enables latent heat storage and release, thereby stabilizing indoor temperatures and reducing overall energy consumption. This study employs transient CFD simulations to propose and assess an innovative wall system incorporating two PCM layers arranged in parallel, specifically tailored to the semi-arid climate of Marrakesh. The novelty of this work lies in the simultaneous parametric analysis of three key design factors: PCM type, thickness, and spatial positioning within the wall. Results indicate that the PCM1 (29 °C) + PCM4 (16 °C) configuration delivers the best performance, reducing indoor temperature fluctuations by over 40 % and lowering annual energy demand by up to 24 % compared to a reference wall without PCMs. Temperature contour analyses revealed a more uniform thermal distribution, while viscosity field visualizations provided valuable insights into the progression of melting and solidification cycles. These findings underscore the strategic role of PCMs as an effective passive solution for enhancing energy efficiency and thermal comfort in hot, arid climates. The study establishes a reproducible and climate-responsive framework tailored to North African conditions, paving the way for the broader adoption of PCMs in sustainable building design.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":"80 ","pages":"Pages 82-98"},"PeriodicalIF":3.1,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145043929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Crystal-liquid interfacial free energy and thermophysical properties of refractory Mo, Nb and Ta pure metal elements","authors":"Yong Chan Cho ,&nbsp;Shraddha Ganorkar ,&nbsp;Lei Wang ,&nbsp;Sangho Jeon ,&nbsp;John Jonghyun Lee ,&nbsp;Yun-Hee Lee ,&nbsp;Geun Woo Lee","doi":"10.1016/j.cap.2025.09.013","DOIUrl":"10.1016/j.cap.2025.09.013","url":null,"abstract":"<div><div>The crystal-liquid interfacial free energy (IFE) plays a crucial role in understanding crystal nucleation and growth phenomena across various scientific research fields. Measuring the IFE is very challenging under high-temperature environments, due to the volatility, reactivity, and contamination of molten metals that can result in ambiguous understanding of nucleation. It has been known that container-free techniques can overcome the experimental difficulties. In this study, we measure thermophysical parameters of the refractory metallic liquids (i.e., Nb, Mo, and Ta) and calculate their IFE. These results will be useful for understanding the fundamentals of nucleation and glass formation under high-temperature environment, as well as for designing new materials.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":"80 ","pages":"Pages 151-157"},"PeriodicalIF":3.1,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145105111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Localized and delocalized electron states in TiO2 revealed using resonant inelastic soft X-ray scattering","authors":"Layla Mravac ,&nbsp;Yi-De Chuang ,&nbsp;Ji Hyeon Choi ,&nbsp;Ji Won Han ,&nbsp;Tae Joo Park ,&nbsp;Kyung Won Park ,&nbsp;Jae Hyuck Jang ,&nbsp;Cheng-Tai Kuo ,&nbsp;Deok-Yong Cho","doi":"10.1016/j.cap.2025.10.005","DOIUrl":"10.1016/j.cap.2025.10.005","url":null,"abstract":"<div><div>Excess carriers in defective TiO₂ play a key role in determining the functionality of numerous applications including photocatalysts, memristors, etc. The electronic structures of the excess electron states derived from inherent oxygen deficiencies in a TiO₂ crystal and a TiO₂ thin film are investigated by using resonant inelastic soft X-ray scattering. The results show that there exist two separable states associated with these excess electrons, that is, either local (bound) or delocalized (band-like) <em>d</em> electrons, and that their abundance differs significantly depending on the sample type. In the case of thin film, delocalized electron states (<em>d</em>-fluorescence) dominate over the localized defect states (<em>dd</em> excitation) showing a strong resonance effect at Ti³⁺’s excitation energy, whereas in the case of crystal, both localized and delocalized electron states weakly contribute to the defect states. Most plausibly, this discrepancy originates mainly from the distinct crystal structure of a rutile (crystal) and an anatase (thin film), implying that understanding the crystal structure dependence of intrinsic defects in TiO₂ polymorphs is crucial for engineering TiO₂'s electronic transport properties.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":"80 ","pages":"Pages 327-332"},"PeriodicalIF":3.1,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145332807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}