Results in Physics最新文献

{"title":"A random fiber laser with multiple bidirectional Rayleigh scattering provided by dual-ring sub-cavity structure","authors":"Shaode Li ,&nbsp;Wei He ,&nbsp;Qiongyue Zhang ,&nbsp;Xingpeng Fei","doi":"10.1016/j.rinp.2025.108151","DOIUrl":"10.1016/j.rinp.2025.108151","url":null,"abstract":"<div><div>In this study, a simple and effective method for enhancing Rayleigh scattering (RS) intensity is proposed and experimentally validated, enabling stable output with exceptionally low-frequency noise across each wavelength channel of random fiber lasers (RFLs). The design employs two segments of single-mode fibers (SMFs) symmetrically arranged in dual-ring sub-cavity. This unique structural configuration facilitates multiple bidirectional RS interactions, providing sufficient random distributed feedback (R-DFB) for the laser system. Initially, random laser (RL) outputs at 1560 nm were achieved using both ring-cavity and single-ring sub-cavity structures. These systems exhibited frequency noise exceeding 1.21 Hz/√Hz and wavelength and output power fluctuations of 0.79 nm and 1.52 dB, respectively. Subsequently, the laser system was upgraded to a dual-ring sub-cavity configuration, and its output performance was re-evaluated. The experimental results show that the wavelength and output power fluctuations are reduced to 0.28 nm and 0.26 dB, respectively. Benefiting from the enhanced R-DFB and superior filtering properties of the dual-ring sub-cavity, the frequency noise of the lasing output decreased significantly to 0.03 Hz/√Hz, the lowest value reported to date. In addition, the importance of sufficient R-DFB for RFL is demonstrated by measuring frequency amplitude, output linewidth, and slope efficiency.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"70 ","pages":"Article 108151"},"PeriodicalIF":4.4,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143395193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Laser-induced photochemical reduction for the production of gold and silver nanoparticles on gold nanostructures","authors":"Naushad Ahmad Khan ,&nbsp;Yi-Han Kuo ,&nbsp;Shang-Yang Yu ,&nbsp;Yun-Cheng Ku ,&nbsp;Kuo-Yung Hung ,&nbsp;Jiunn-Woei Liaw","doi":"10.1016/j.rinp.2025.108152","DOIUrl":"10.1016/j.rinp.2025.108152","url":null,"abstract":"<div><div>This research explores two methods for the photo-chemical reduction of gold and silver ions, utilizing either a continuous-wave (CW) laser or a femtosecond laser, in conjunction with plasmon-assisted hot electrons. The study focuses on the photoreduction of chloroauric acid (HAuCl₄) and silver nitrate (AgNO₃) solutions containing gold nanostructures under irradiation from either CW or femtosecond laser. Specifically, we employed a 445 nm CW laser to irradiate gold nanowires, formed through the photo-driven self-assembly of gold nanorods, in HAuCl₄ solution. Through this photoreduction process, we observed the newly formed gold nanoparticles on the surface of gold nanowires. In addition, we also used 445 nm to irradiate gold triangular nanoplates in AgNO₃ solution with ascorbic acid as a reducing agent. We observed that silver nanoparticles clearly formed and attached to the edges of a gold triangular nanoplate. In another approach, an 800 nm femtosecond laser was used to irradiate gold nanorods, gold triangular/hexagonal nanoplates and a gold nanofilm in AgNO₃ solution with a reducing agent under inverted microscopy. For instance, silver nanoparticles were observed to attach to the edges of the gold triangular and hexagonal nanoplates, facilitating the growth of the nanoplates. The formation of photochemically reduced nanoparticles was confirmed using energy-dispersive X-ray spectroscopy. Notably, 3D silver dendritic structures were synthesized with the femtosecond laser and deposited onto the gold nanofilm, a process attributed to two-photon absorption effect. The high sensitivity of these immobilized dendrites for surface-enhanced Raman scattering applications was also demonstrated.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"70 ","pages":"Article 108152"},"PeriodicalIF":4.4,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143420691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pressure-induced modifications in the electronic, mechanical, optical, and thermodynamic properties of CsPbI3 for advanced optoelectronic applications: A DFT study","authors":"Mehrunisa Moin ,&nbsp;A. Qadoos ,&nbsp;Muhammad Moin ,&nbsp;Urva Gull ,&nbsp;Muhammad Rashid ,&nbsp;Zhenyi Jiang ,&nbsp;Udayabhasakrarao Thumu","doi":"10.1016/j.rinp.2025.108150","DOIUrl":"10.1016/j.rinp.2025.108150","url":null,"abstract":"<div><div>Halide perovskite-based materials have garnered significant attention in the scientific community due to their diverse optoelectronic and photovoltaic applications. This study employed density functional theory (DFT) to investigate the substantial changes in the physical properties of cubic halide perovskite CsPbI₃ under hydrostatic pressures ranging from 0 to 55 GPa. Under high external pressures, CsPbI₃ transitions from semiconducting to metallic, with conduction and valence band maxima convergent at 40 and 55 GPa. The intrinsic structure of CsPbI₃ exhibits direct band gap tuning at the Γ point, decreasing with pressure and reaching optimal photoelectric efficiency values (1.30–1.40 eV) within the 35–45 GPa range. Bandgap modifications alter state density, impacting conduction and valence band contributions. The mechanical response of CsPbI₃ shows its ductile behavior and ability to improve properties under external pressure. Elastic coefficients increase at a maximum pressure value, indicating stiffness and resistance to shear deformation. However, when pressure exceeds 45 GPa, the phenomenon of phase stability sharply breaks down. Furthermore, dynamic dielectric functions are often used to measure the impact of band gap reduction on optical properties and illustrate that the pressure increases lead to a rise in the behavior of static refractive index. The optical absorption peak of CsPbI₃ exhibits a redshift with growing pressure, attributed bandgap reduction, and demonstrates enhanced light absorption and conductivity. The thermodynamic analysis examines phonon dispersion, lattice vibrations, and thermal conductivity. The results show structural stability under pressures from 0 to 45 Pa, highlighting CsPbI₃’s suitability for heat-dissipating applications. These findings suggest that CsPbI₃ has significant potential for advanced optoelectronic applications, particularly in the development of efficient photovoltaic materials that leverage its unique properties under pressure.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"70 ","pages":"Article 108150"},"PeriodicalIF":4.4,"publicationDate":"2025-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143395191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simulation research of thermionic emission process and impact of voltage parameters in the three-pole electron gun","authors":"Haoyang Hu ,&nbsp;Yue Zhao ,&nbsp;Pengcheng Shang ,&nbsp;Feibin Zhang ,&nbsp;Aiping Wu ,&nbsp;Haiyan Zhao ,&nbsp;Lihang Li","doi":"10.1016/j.rinp.2025.108142","DOIUrl":"10.1016/j.rinp.2025.108142","url":null,"abstract":"<div><div>The three-pole electron gun is composed of cathode, anode and grid electrode, which can effectively control the emission beam current and is widely used in welding and additive manufacturing equipment. However, the characteristics of the emission beam and the process of beam control have yet to be fully and accurately elucidated. Considering that the characteristics of the electron beam at the emission stage have a significant effect on the beam quality, the electric field distribution and electron beam trajectory at the emission stage are studied based on the simulation method of bidirectionally coupled particle tracing. The results show that a spatial potential barrier several tens of microns high is formed on the cathode surface. The different relative potential across the barrier at different positions leads to the non-uniform effective emission beam density of the cathode. With the increase of bias voltage, the effective emission area and emission beam density decrease simultaneously. The average emission beam density varies with the accelerating voltage, which does not follow the Child-Langmuir law, but exhibits a more significant trend of variation. The present work proposes a modified formula suitable for the three-pole electron gun for calculating the average emission beam density, obtaining good fitting results.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"70 ","pages":"Article 108142"},"PeriodicalIF":4.4,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143437361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Topological indices and their correlation with structural properties of carbon nanotube Y-junctions","authors":"Khawlah Alhulwah ,&nbsp;Ali N.A. Koam ,&nbsp;Nasreen Almohanna ,&nbsp;Muhammad Faisal Nadeem ,&nbsp;Ali Ahmad","doi":"10.1016/j.rinp.2025.108141","DOIUrl":"10.1016/j.rinp.2025.108141","url":null,"abstract":"<div><div>Carbon nanotubes (CNTs) are tubular nanoforms of carbon atoms arranged in a hexagonal lattice, and junction formation imparts new functionalities to these tubes. Among the various types, Y-junctions, in which a single CNT splits into a Y-shaped structure, have particular importance in nanoelectronics and logic devices due to their special structural and electronic properties. In this work, the calculation of the Balaban, Forgotten, and Zagreb indices for the four types of CNT Y-junctions is carried out using chemical graph theory. The obtained results clearly show that all these topological indices increase progressively across the different configurations of the Y-junctions, which evidences a direct relationship among the structural complexity and stability with their electronic properties.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"70 ","pages":"Article 108141"},"PeriodicalIF":4.4,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143351381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reconfigurable group delay with tunable topological edge state based on phase transitions material Ge2Sb2Te5 in dual-band","authors":"Yao Lu ,&nbsp;Qiaohong Yao ,&nbsp;Mengdong He ,&nbsp;Jiao Xu ,&nbsp;Yuxiang Peng","doi":"10.1016/j.rinp.2025.108145","DOIUrl":"10.1016/j.rinp.2025.108145","url":null,"abstract":"<div><div>We investigate reconfigurable reflected group delay in dual-band of the photonic crystal heterostructure containing phase transitions material Ge₂Sb₂Te₅ and graphene in mid-infrared region. The giant phase change of reflected beam derives from the topological edge state excited at the boundary surface of photonic crystal. Meanwhile, the tunable topological edge states can be satisfied by controlling the reversible switching between the crystalline and amorphous states of the Ge₂Sb₂Te₅, which provides a flexible way to achieve configurable group delay in dual-band. Besides, the reflected group delay can be dynamically controlled by controlling Fermi energy, relaxation time of graphene and the incident angle. The reconfigurable reflected group delay in dual-band presented in this paper has the potential to be used in high-efficiency memory for optical pulses and optical delay lines.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"70 ","pages":"Article 108145"},"PeriodicalIF":4.4,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143351379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The molecular dynamics study of the thermal behavior of argon flow in a nanochannel with changes in nanochannel cross-section","authors":"Reza Karimi ,&nbsp;Ali Marzban ,&nbsp;Davood Toghraie","doi":"10.1016/j.rinp.2025.108143","DOIUrl":"10.1016/j.rinp.2025.108143","url":null,"abstract":"<div><div>This article investigates argon Poiseuille flow through a copper two- and three-dimensional nanochannel via molecular dynamics simulation. In recent studies, changes in the flow cross section and the presence of solid walls in the nanochannel have been less investigated. This study investigated the influence of lateral walls in two- and three-dimensional systems, an external force, velocity field, density, temperature, flux, and thermal conductivity coefficient for a 10000-time increment using a hybrid Lennard-Jones potential function. The modeling of this research was carried out to investigate the behavior of argon flow in two- and three-dimensional nanochannels. This research is simulated in three-dimensional space using molecular dynamics methods using computer code. The results of this research show that, the increase in the number of wall atoms in a three-dimensional nanochannel causes a greater depletion of fluid kinetic energy due to the loss of temperature. The growth rate is denser in the central region of the three-dimensional nanochannel than in its two-dimensional counterpart. For square and rectangle nanochannels in the two-dimensional mode, widening the flow causes reduced density variations and minimal impact on density oscillations. In the square nanochannel, due to the small section, argon-argon and argon-copper interatomic contrasts will make the velocity of fluid atoms dominate and will make the axial velocity component more significant in the rectangle section. According to collision and diffusion mechanisms which distribute and exchange heat, there will be limited changes by altering the nanochannel section from square to rectangle. It seems that this behavior is due to similar atomic contrasts for argon-argon and argon-copper atoms. Increasing the flow section along the nanochannel transverse direction, the heat exchange caused by the interatomic collision mechanism in regions beside the wall increases, because the section increases by 20%.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"70 ","pages":"Article 108143"},"PeriodicalIF":4.4,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143371725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental implementation of a non-ideal three-waveplate array as a polarization disturbance corrector","authors":"J.A. Jiménez-Arias ,&nbsp;M. Vázquez-Ibarra ,&nbsp;S.A. Salazar-Altamirano ,&nbsp;P. Moreno-Martínez ,&nbsp;J.M. López-Romero ,&nbsp;K. Jiménez-García ,&nbsp;N.V. Corzo","doi":"10.1016/j.rinp.2025.108135","DOIUrl":"10.1016/j.rinp.2025.108135","url":null,"abstract":"<div><div>Polarization disturbance is a significant source of error in polarization-based experiments, where an input state is unpredictably transformed into an unintended state due to the birefringence of optical media. A solution to this problem is the implementation of a polarization disturbance corrector based on a three-waveplate array. In this work, we propose a theoretical framework to derive the analytical expressions of the correction parameters for a three-waveplate array with retardance <span><math><mrow><mo>(</mo><msub><mrow><mi>η</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>,</mo><msub><mrow><mi>η</mi></mrow><mrow><mn>2</mn></mrow></msub><mo>,</mo><msub><mrow><mi>η</mi></mrow><mrow><mn>3</mn></mrow></msub><mo>)</mo></mrow></math></span>, along with an experimental method that requires only a single polarization measurement basis. The proposed theoretical framework, based on the mathematical treatment of polarization and its relation with the mathematical structure of the SU(<span><math><mn>2</mn></math></span>) Lie group, reveals the fundamental role of the transformations performed by a three-waveplate array in correcting polarization disturbances while analytical expression are deduced. Furthermore, we validate the theoretical derived expressions by implementing a three-waveplate array with retardances close to <span><math><mrow><mo>(</mo><mi>π</mi><mo>/</mo><mn>2</mn><mo>,</mo><mi>π</mi><mo>/</mo><mn>2</mn><mo>,</mo><mi>π</mi><mo>)</mo></mrow></math></span> in an experimental scenario, successfully compensating for polarization disturbance introduced by a single-mode optical fiber. The experimental results were evaluated through the calculation of polarization state fidelities, achieving values approaching unity. The experimental method presented in this work enables a precise correction to polarization disturbance as well as an enhancement of the robustness of experiments involving polarization against external variables that affect birefringent media. Our work sets the theoretical and experimental foundations for developing automated optical correction systems with precise polarization control in polarization-based experiments.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"70 ","pages":"Article 108135"},"PeriodicalIF":4.4,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143376611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An analytical investigation of nonlinear time-fractional Schrödinger and coupled Schrödinger–KdV equations","authors":"Yogeshwari F. Patel ,&nbsp;Mohammad Izadi","doi":"10.1016/j.rinp.2025.108137","DOIUrl":"10.1016/j.rinp.2025.108137","url":null,"abstract":"<div><div>This study applies the Fractional Reduced Differential Transform Method (FRDTM) to solve two nonlinear fractional equations: the time-fractional Schrödinger equation (TFSE) and the coupled Schrödinger–KdV (Sch–KdV) equation, which are prominent in quantum mechanics, plasma physics, and wave propagation studies. These equations model various wave phenomena, including dust-acoustic waves, electromagnetic waves, and Langmuir waves, in plasma physics. Using the Liouville–Caputo fractional derivative, FRDTM effectively incorporates nonlocality and memory effects. The solutions are derived as rapidly convergent infinite series with terms that are straightforward to compute, ensuring both accuracy and efficiency. Numerical examples highlight the method’s ability to closely approximate exact solutions, with graphical and tabular comparisons illustrating the effect of the fractional order on solution behavior and validating the approach through computed absolute errors. Additionally, discussions on the modulation instability of the models reinforce the robustness of FRDTM as a powerful tool for solving complex nonlinear fractional systems.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"70 ","pages":"Article 108137"},"PeriodicalIF":4.4,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143351380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantum mechanical insights into Edge-Dependent electronic properties of phosphorene nanoribbons","authors":"Mohammadamir Bazrafshan ,&nbsp;Adeleh Vatankhahan ,&nbsp;Farhad Khoeini ,&nbsp;Omid Farzadian","doi":"10.1016/j.rinp.2025.108140","DOIUrl":"10.1016/j.rinp.2025.108140","url":null,"abstract":"<div><div>Phosphorene, known for its anisotropic physical properties, exhibits a direct moderate electronic band gap, making it a candidate for electronic applications. This study investigates the electronic properties of phosphorene nanoribbons (PNRs) with different edge configurations using density functional theory (DFT). It addresses the role of sublattices in zigzag and armchair phosphorene nanoribbons, identifying six different edge configurations for zigzag and two for armchair edges. The density of states (DOS) at the valence band maximum (VBM) can be strongly different on the sublayers in some zigzag edge configurations, which can be useful in many applications such as sensing. Conversely, the conduction band minimum (CBM) shows low sensitivity to the edge configuration, indicating that electron transport can be less affected than hole transport. The electronic band gap of both armchair and zigzag nanoribbons decreases with increasing width, which also varies with edge type. Armchair nanoribbons undergo compressive strain, while zigzag nanoribbons experience tensile stress compared to the corresponding directions in phosphorene. These findings provide insight into the design of phosphorene-based nanodevices, including transistors, sensors, and flexible electronics.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"69 ","pages":"Article 108140"},"PeriodicalIF":4.4,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143315417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}