Journal of the Korean Physical Society最新文献

{"title":"Publisher Erratum: Nonlinear shock dynamics in charge-fluctuating dusty plasmas: the role of viscosity and mobility","authors":"Noor Ahmad Nayan, M. Himel Azad, M. Masum Haider","doi":"10.1007/s40042-025-01325-6","DOIUrl":"10.1007/s40042-025-01325-6","url":null,"abstract":"","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"86 7","pages":"692 - 692"},"PeriodicalIF":0.8,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749057","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":"Influence of diverse dielectric materials on the performance of enhancement-mode AlGaN/GaN MISHEMTs with a β-Ga2O3 buffer and substrate for RF and power applications","authors":"Sivamani Chinnaswamy,&nbsp;Gowtham Palanirajan,&nbsp;N. Vigneshwari,&nbsp;Jayasheela Moses,&nbsp;Ramkumar Natarajan,&nbsp;P. Murugapandiyan","doi":"10.1007/s40042-025-01318-5","DOIUrl":"10.1007/s40042-025-01318-5","url":null,"abstract":"<div><p>In this study, we have investigated the influence of diverse dielectric materials on the performance of enhancement-mode AlGaN/GaN MISHEMTs using a β-Ga₂O₃ buffer and substrate. By employing a range of dielectrics (SiO₂ (<i>ε</i>_r = 3.9), SiN (<i>ε</i>_r = 7.5), Al₂O₃ (<i>ε</i>_r = 9.8), HfO₂ (<i>ε</i>_r = 25), La₂O₃ (<i>ε</i>_r = 27), and TiO₂ (<i>ε</i>_r = 80)) for gate oxide and surface passivation, we aimed to explore their effects on device characteristics and identify trade-offs associated with their implementation. β-Ga₂O₃ has a wide bandgap (4.8 eV for β-phase), which is compatible with GaN (3.4 eV).The β-Ga₂O₃ substrates and the buffers can potentially be produced in larger sizes with good wafer quality and fewer defects compared to traditional GaN buffers and other substrates such as sapphire or silicon carbide (SiC). The dielectrics SiO₂ (TiO₂) delivered a drain current of 2.54 (2.79) A/mm, a transconductance of 0.33 (0.54) S/mm, a cut-off frequency of 47 (21) GHz for a drain voltage 20 V, an ON resistance of 1.56 (0.96) Ω mm, a breakdown voltage of 1012 (1906) V, and an intrinsic time delay of 0.84 (0.68) pico-seconds. The proposed device with a SiN (<i>ε</i>_r = 7.5) insulator exhibited the highest JFOM (<i>V</i>_BR × <i>f</i>_T) of 50.34 THz-V. This study paves the road for selecting the appropriate insulator for next-generation RF and power applications.</p></div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"86 7","pages":"678 - 691"},"PeriodicalIF":0.8,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749090","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":"Comprehensive analysis of structural and elastic properties of SnTe: insights from LDA, GGA and PBEsol calculations with density functional theory","authors":"Seram Rebika Devi,&nbsp;B. Indrajit Sharma","doi":"10.1007/s40042-025-01310-z","DOIUrl":"10.1007/s40042-025-01310-z","url":null,"abstract":"<div><p>This study presents a thorough analysis of the structural and elastic properties of SnTe employing the local density approximation (LDA), generalized gradient approximation (GGA) and PBEsol-GGA exchange-correlation potentials in light of density functional theory (DFT) with WIEN2k code. The optimized structural lattice parameters of SnTe correlate well with the previously calculated theoretical and experimental results. From the computed elastic constants using IRelast package, the material’s mechanical stability is verified. Based on the elastic constants, we acquire several elastic properties of the material. Elastic anisotropy is also evident in SnTe as shown by significant deviations in shear anisotropy factors (<span>(A_1, A_2, A_3)</span>) and universal anisotropy factor (<span>(A^U)</span>) revealing the directional dependencies within the crystal bonding structure. The machinability index and Vickers hardness measurements show that SnTe has favorable machinability and moderate hardness making it well-suited for various industrial applications. Additionally, key thermodynamic parameters including Debye temperature, average wave velocity, transverse and longitudinal elastic wave velocities, melting temperature, etc. are calculated.</p></div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"86 7","pages":"656 - 664"},"PeriodicalIF":0.8,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749089","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":"Cattaneo-Christov heat flux in MHD Ree-Eyring nanofluid flow via porous medium including entropy optimization and gyrotactic microorganism","authors":"M. Vinodkumar Reddy,&nbsp;Jintu Mani Nath,&nbsp;K. Ramakrishna Reddy,&nbsp;Tusar Kanti Das,&nbsp;K. Venugopal Reddy","doi":"10.1007/s40042-025-01316-7","DOIUrl":"10.1007/s40042-025-01316-7","url":null,"abstract":"<div><p>The proposed study aims to perform an extensive numerical analysis of the Cattaneo-Christov heat flux model for the magnetohydrodynamic (MHD) flow of Ree-eyring nanofluid through a Darcy-Forchheimer porous medium. This analysis will integrate the effects of Activation energy, gyrotactic microorganisms, entropy optimization, Brownian motion, and Thermophoresis, with a particular focus on the dynamics of flow over a stretching surface. Utilizing the Buongiorno nanofluid model, the research will explore the complex interactions within fluid flow. This investigation is pioneering in its approach, as it combines intricate factors such as heat flux modelling, non-Newtonian fluid behaviour, entropy generation, microbial dynamics, and nano-model effects into a unified numerical framework. By addressing these multifaceted elements, the study aims to advance the understanding of heat and mass transfer in sophisticated fluid systems. The ongoing investigation is conducted using a numerical approach using the bvp5c MATLAB package. The findings are expected to enhance thermal management strategies across diverse applications, including aerospace engineering, electronic cooling, energy systems, and biomedical technologies. It is observed that The Cattaneo-Christov heat flux model, considering finite thermal relaxation, reduces heat distribution promptly. Furthermore, enhanced Lorentz force, Brownian motion, and radiation diffuse heat significantly, while thermophoresis and activation energy boost mass distribution. Also, Increased Peclet and bioconvection Lewis numbers lead to higher motile density due to stronger convection and thermal diffusion. The entropy generation also looks promising with the enhancement in Lorentz force, diffusion factor, Brinkman number, and temperature difference factor.</p></div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"86 7","pages":"615 - 635"},"PeriodicalIF":0.8,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749091","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":"Role of a helium catalyzed process and deuteron beam radiation simultaneously on the D3He target to create supplementary fusion energy","authors":"N. Niknam,&nbsp;S. N. Hosseinimotlagh,&nbsp;M. Eshghi,&nbsp;Z. Parang","doi":"10.1007/s40042-025-01309-6","DOIUrl":"10.1007/s40042-025-01309-6","url":null,"abstract":"<div><p>The energy enhancement required for fusion through ICF can be achieved through fast ignition as a good method. The use of deuteron beams and injected into the fusion plasma containing D³He increases the amount of fusion reactor fuel and the deuteron beam causes the fast ignition. The incident deuteron beam stopping power in the desired fusion plasma is higher than that of the electron. Therefore, they can create a higher energy density by stopping at a smaller volume of fuel, and it produces supplementary energy. Note that another advantage of using a deuteron beam is that it reduces the energy of the required laser beams. This issue can play a significant role in increasing the efficiency of commercial fusion reactors. In this work, we have calculated the amount of deposited energy or the produced supplementary energy due to deuteron beam radiation and performing fusion reactions. However, in the ICF approach, using pure D³He fuel is impractical due to the excessive requirement for ignition energy. Therefore, a small amount of DT fuel is necessary as an “igniter”. Since the D³He reaction does not produce any neutrons and the fuel sources of the DD fusion reaction are available in sufficient quantity in Earth, it is expected that these reactions can be used as a source of clean energy. The process of helium catalyzed D³He is the primary focus of advanced fuel fusion reactors. In this article, we determined the fusion energy gain, G, from the solving of time-dependent non-linear point kinetic differential equations coupled together for two processes with and without helium catalyzed process. The results of this study have shown that G gradually increases with increasing temperature, and at a temperature of 190 keV, the value of G reaches its maximum value, so that at this temperature, for the two states without and with the helium catalyzed process, the G value reaches about 20 and 110, respectively, which shows that considering the helium catalyzed process simultaneously deuteron beam radiation provides access to supplementary energy and finally G increases.</p></div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"86 7","pages":"636 - 648"},"PeriodicalIF":0.8,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749088","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":"Cosmology of Higgs-coupled axions","authors":"Kwang Sik Jeong","doi":"10.1007/s40042-025-01313-w","DOIUrl":"10.1007/s40042-025-01313-w","url":null,"abstract":"<div><p>An intriguing interaction of axions, which are naturally expected to be light and weakly interacting due to their shift symmetry, is their coupling to the Higgs boson. This interaction has significant implications for the electroweak phase transition and could facilitate electroweak baryogenesis. By incorporating a temperature-dependent axion potential arising from Higgs thermal fluctuations, we investigate how the axion-Higgs coupling modifies the electroweak phase transition. Furthermore, we explore the cosmological aspects of axions, including their cosmic evolution, thermalization processes, and their potential role in dark matter production.</p></div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"86 7","pages":"585 - 594"},"PeriodicalIF":0.8,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749137","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":"Two-dimensional MoS2-based artificial synaptic transistor for neuromorphic computing","authors":"Jeongyeol Park,&nbsp;Moonsang Lee","doi":"10.1007/s40042-025-01315-8","DOIUrl":"10.1007/s40042-025-01315-8","url":null,"abstract":"<div><p>Although transition metal dichalcogenide (TMDC) materials are increasingly recognized for their potential in neuromorphic computing, their use as channel materials in field-effect transistors (FETs) remains elusive. This study examined the use of 2D molybdenum disulfide (MoS₂) to fabricate an artificial synaptic transistor, leveraging its unique semiconducting properties to emulate synaptic functions. The synaptic transistor exploits gate-triggered resistive switching mechanisms inherent to 2D MoS₂. This enables the transistor to replicate key synaptic behaviors such as excitatory and inhibitory postsynaptic currents, potentiation and depression, and paired-pulse facilitation. Its ability to serve as an artificial synapse with multiple stable conductance states, outstanding linearity, and low-power consumption was confirmed by modulating the conductance states of the FET. Extensive artificial neural network (ANN) simulations were performed using binary MNIST dataset digits, with 784 input neurons corresponding to 28 × 28 pixel images and 10 output neurons. Training on 42,000 MNIST digits and updating synaptic weights with conductance values derived from 18,000 training samples achieved an impressive recognition rate on the testing data. These findings highlight the potential of 2D MoS₂-based FETs in advancing neuromorphic hardware systems, offering robust synaptic functionality and effective learning rules for complex neural network applications.</p></div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"86 7","pages":"649 - 655"},"PeriodicalIF":0.8,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749138","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":"Domain wall velocity prediction in magnetic nano stripe under spin-polarized current using machine learning techniques","authors":"Madhurima Sen,&nbsp;Saswati Barman","doi":"10.1007/s40042-025-01312-x","DOIUrl":"10.1007/s40042-025-01312-x","url":null,"abstract":"<div><p>High domain wall velocity in magnetic nano stripe is a topic of interest in developing more sophisticated devices for neuromorphic computing and storage. A micromagnetic simulation is an excellent tool for investigating spin dynamics and calculating domain wall velocity, but this process is very time-consuming. So, a computational model has been developed to predict the spin dynamics. The domain wall velocity at different current densities has been generated from the time domain data obtained from the micromagnetic simulation. This data is used to train various machine-learning models. We have explored the Echo State Network (ESN), Long Short-Term Memory (LSTM) model, Seasonal Autoregressive Integrated Moving Average with Exogenous Factor (SARIMAX), and Neural Basis Expansion Analysis Time Series (N-BEATS) forecasting model to predict the domain wall velocity from the post-processed sequence data. We found that Echo State Network outperforms all other models in a small dataset. Echo State Network models achieve a lower Normalized Root Mean Squared Error (NRMSE) of 0.785 and Mean Absolute Percentage Error (MAPE) of 0.083 than the other three models. From the present work, we concluded that ESN is a suitable computational model for predicting the domain wall velocity that follows non-linear spin dynamics.</p></div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"86 7","pages":"665 - 677"},"PeriodicalIF":0.8,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749092","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":"Relativistic coordinate transformation for circular motion in arbitrary inertial frame","authors":"Yang-Ho Choi","doi":"10.1007/s40042-024-01268-4","DOIUrl":"10.1007/s40042-024-01268-4","url":null,"abstract":"<div><p>A world system is composed of the world lines of observers at rest in the system. The transformation under the constant light speed (TCL), which provides a relativistic transformation between the unique isotropic world system and a rotating world system, can effectively deal with circular motions. Under the unique isotropic frame, the general framework of Mansouri–Sexl (MS) enables us to handle rectilinear motions. Through a derivation based on the MS framework in the standard synchronization, this paper extends the TCL, such that it can also be applied to an arbitrary inertial world system. Circular motions can be considered to be locally and momentarily inertial. Speeds of light in inertial frames are found using the derived TCL via limit operations. It is shown that when a light beam traverses a closed loop in an inertial frame, its average speed is constant, which is consistent with the experiment of Michelson and Morley. Exploiting the TCL, we comprehensively analyze the generalized Sagnac effect in an anisotropic laboratory frame. The analyses include the speeds of light in the rotating frame, not only in the collinear case but also the non-collinear case where the propagation direction of light is not collinear with the direction of fiber motion.</p></div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"86 7","pages":"575 - 584"},"PeriodicalIF":0.8,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749055","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":"Numerical modeling of gain-switched dysprosium-doped yellow fiber lasers","authors":"Iffat Ara Talin,&nbsp;Md. Ziaul Amin,&nbsp;Md. Abdus Samad","doi":"10.1007/s40042-025-01303-y","DOIUrl":"10.1007/s40042-025-01303-y","url":null,"abstract":"<div><p>Compact and cost-effective pulsed yellow lasers have a growing demand for important medical applications including eye treatment, dermatology, and novel biomedical imaging. However, the efficient pulsed yellow light generation from a compact laser structure has historically been quite challenging. Recently, a dysprosium (<span>(hbox {Dy}^{3+})</span>)-doped fiber laser has emerged as a promising candidate to produce yellow light directly and efficiently, paving the way for a simple and compact source. To date, major attention has been paid to the design of continuous wave (CW) <span>(hbox {Dy}^{3+})</span>-doped yellow fiber lasers. Here, we report, to the best of our knowledge, the first numerical investigation on the pulse-generating potential of a <span>(hbox {Dy}^{3+})</span>-doped fiber laser using a convenient gain-switching technique. With a particular emphasis on future experimental demonstrations, we consider the parameters of a commercially available <span>(hbox {Dy}^{3+})</span>-doped ZBLAN fiber and utilize a 450 nm pumping wavelength, which can be accessed from commercial laser diodes. In our investigation, we use a feasible peak pump power of 4 W and simulate a peak yellow output power of 11 W with a minimum pulse width (full width at half maximum) of 0.8 <span>(upmu)</span>s at a pulse repetition rate of 25 kHz. In a <span>(hbox {Dy}^{3+})</span>-doped ZBLAN fiber, the lower level (<span>(^6)</span>H<span>(_{13/2})</span>) of the yellow lasing transition has a comparable lifetime (650 <span>(upmu)</span>s) to that of the upper laser level (<span>(^4)</span>F<span>(_{9/2})</span>). Therefore, we also analyze the impact of the lower laser level lifetime on the gain-switching laser performance and discuss the further developmental potential.</p></div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"86 7","pages":"595 - 604"},"PeriodicalIF":0.8,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749073","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}