IF 2.1 4区物理与天体物理

Pramana Pub Date : 2025-07-30 DOI: 10.1007/s12043-025-02943-2

R Surendar, M Saraswathy, Ahmed Kadhim Hussein

{"title":"Asymptotic stability and sampled data control of hybrid nanofluid in a time-delay nonlinear Brinkman system","authors":"R Surendar, M Saraswathy, Ahmed Kadhim Hussein","doi":"10.1007/s12043-025-02943-2","DOIUrl":"10.1007/s12043-025-02943-2","url":null,"abstract":"<div><p>Our approach in the present work is concerned with a novel study involving a sampled-data controller for hybrid nanofluid in a time-delay nonlinear Brinkman system with randomly occurring uncertainties. The time-delay error system is described by utilising a hybrid nanofluid in nonlinear system and the looped Lyapunov–Krasovskii functional with a splitting sampling interval. In order to ensure that the resulting closed-loop system is reliable, it is asymptotically stable and has the required dissipative efficiency. A master/slave synchronisation technique is employed to synchronise the hybrid nanofluid in nonlinear system. In addition, we employed a sampling interval <span>([t_{k}, t_{k+1}])</span> and the fractional parameter <span>({tilde{beta }})</span> in the interval [0,1] has split into <span>([t_{k}, t_{k} +{tilde{beta }} varsigma _{1}(t)], [ t_{k} +{tilde{beta }} varsigma _{1}(t), t], [t, t +{tilde{beta }} varsigma _{2}(t)])</span> and <span>( [ t +{tilde{beta }} varsigma _{2}(t), t_{k+1}])</span>. Then, the synchronised hybrid system utilises the looped Lyapunov stability theory and positive definite matrix. The simulation results not only confirm the theoretical predictions but also demonstrate enhanced control performance, improved synchronisation accuracy and robust dynamic stability. Furthermore, this study highlights the impact of time-delay, uncertainty and fractional parameter variations on system stability. The proposed approach provides a new direction for advanced control strategies in nanofluid-based nonlinear systems, offering potential applications in engineering and industrial processes. Finally, certain simulation results verify the effectiveness and correctness of the analytical results.</p></div>","PeriodicalId":743,"journal":{"name":"Pramana","volume":"99 3","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145171772","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}

引用次数: 0

Simulation analysis of a multi-hot-spot system for SERS detection of the nanoplastics 纳米塑料SERS多热点检测系统仿真分析

IF 2.1 4区物理与天体物理

Pramana Pub Date : 2025-07-30 DOI: 10.1007/s12043-025-02979-4

Junhui Zhu, Wei Su, Zhenfeng Wang, Qihang Wan, Cheng Yin

{"title":"Simulation analysis of a multi-hot-spot system for SERS detection of the nanoplastics","authors":"Junhui Zhu, Wei Su, Zhenfeng Wang, Qihang Wan, Cheng Yin","doi":"10.1007/s12043-025-02979-4","DOIUrl":"10.1007/s12043-025-02979-4","url":null,"abstract":"<div><p>In recent years, nanoplastics have attracted increasing attention due to their widespread presence in the environment and potential harm to living organisms. To provide a theoretical basis for using surface-enhanced Raman spectroscopy (SERS) mechanism to detect nanoplastics of different sizes, this work employed lasers to irradiate the substrate composed of a bowl-shaped particle-in-cavity structure and nanoplastics. Then, the electric field distribution was obtained using the finite-difference time-domain (FDTD) method. By altering the curvature of the Ag nanobowl and the size of gold nanoparticles (AuNPs), the electric field enhancement capability of this SERS structure can be ameliorated. It is found that when the diameter of AuNPs is 30 nm, the larger the nanoplastics, the more suitable the structure with smaller curvature as a substrate. But when the diameter of AuNPs is 40 nm, the larger the nanoplastics, the more suitable the structure with larger curvature as a substrate. AuNPs with a size of 40 nm are generally superior to those with a size of 30 nm. To verify the feasibility of this SERS structure for detecting various nanoplastics, we tested a range of nanoplastic materials. The results prove that the materials of nanoplastics will not have a significant impact on the detection. Moreover, a multi-hot-spot system is analysed to reveal the SERS signal enhancement mechanism. A laser of 785 nm can produce stronger ‘localised hot spots’ (LHSs) and weaker ‘volume hot spots’ (VHSs) than a laser of 532 nm. The issue of nanoplastic detection is optimistically poised for resolution, as the hot spots within the bowl-shaped particle-in-cavity structure can effectively approach and surround nanoplastics, stimulating highly intense SERS signals that demonstrate their promising application in nanoplastic detection.</p></div>","PeriodicalId":743,"journal":{"name":"Pramana","volume":"99 3","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145171773","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}

引用次数: 0

Certified quantumness via single-shot temporal measurements 通过单次时间测量验证量子

IF 2.1 4区物理与天体物理

Pramana Pub Date : 2025-07-28 DOI: 10.1007/s12043-025-02986-5

Md Manirul Ali, Sovik Roy

{"title":"Certified quantumness via single-shot temporal measurements","authors":"Md Manirul Ali, Sovik Roy","doi":"10.1007/s12043-025-02986-5","DOIUrl":"10.1007/s12043-025-02986-5","url":null,"abstract":"<div><p>Bell–Kochen–Specker theorem states that a non-contextual hidden-variable theory cannot completely reproduce the predictions of quantum mechanics. Asher Peres gave a remarkably simple proof of quantum contextuality in a four-dimensional Hilbert space of two spin-1/2 particles. Peres’ argument is enormously simpler than that of Kochen and Specker. Peres contextuality demonstrates a logical contradiction between quantum mechanics and non-contextual hidden variable models by showing an inconsistency when assigning non-contextual definite values to a certain set of quantum observables. In this work, we present a similar proof in time with a temporal version of the Peres-like argument. In analogy with the two-particle version of Peres’ argument in the context of spin measurements at two different locations, we examine here single-particle spin measurements at two different times <span>(t=t_1)</span> and <span>(t=t_2)</span>. We adopt three classical assumptions for time-separated measurements, which are demonstrated to conflict with quantum mechanical predictions. Consequently, we provide a non-probabilistic proof of certified quantumness in time, without relying on inequalities, demonstrating that our approach can certify the quantumness of a device through single-shot, time-separated measurements. Our results can be experimentally verified with the present quantum technology.\u0000</p></div>","PeriodicalId":743,"journal":{"name":"Pramana","volume":"99 3","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145170079","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}

引用次数: 0

Microwave-controlled cross-Kerr effect in an X-type atomic system x型原子体系中微波控制的交叉克尔效应

IF 2.1 4区物理与天体物理

Pramana Pub Date : 2025-07-25 DOI: 10.1007/s12043-025-02962-z

Abhishek Verma, Amanjot Kaur, Harjeet Kaur, Sukhdeep Kaur, Paramjit Kaur

引用次数: 0

Predicting suitable optoelectronic, mechanical and transport properties of phosphide crystals for energy applications using accurate first-principles computations 使用精确的第一性原理计算预测适合于能量应用的磷化物晶体的光电、机械和输运性质

IF 2.1 4区物理与天体物理

Pramana Pub Date : 2025-07-25 DOI: 10.1007/s12043-025-02973-w

Muhammad Irfan, Fatma A Ibrahim, Mohamed S Hamdy, Shams A M Issa, H M H Zakaly

{"title":"Predicting suitable optoelectronic, mechanical and transport properties of phosphide crystals for energy applications using accurate first-principles computations","authors":"Muhammad Irfan, Fatma A Ibrahim, Mohamed S Hamdy, Shams A M Issa, H M H Zakaly","doi":"10.1007/s12043-025-02973-w","DOIUrl":"10.1007/s12043-025-02973-w","url":null,"abstract":"<div><p>Photovoltaic materials are highly effective for solar cells, offering high efficiency and stability. Quantum theoretical analysis of phosphides [Sr<sub>3</sub>Sn<sub>2</sub>P<sub>4</sub>]: Eu<sup>3+</sup> for their potential in photovoltaic applications is reported here for the first time. Quantum computations for Sr<sub>3</sub>Sn<sub>2</sub>P<sub>4</sub> optoelectronics, mechanical and transport properties were performed using the all-electron method. The calculations were performed using the generalised gradient approximation plus Hubbard potential U (GGA + U) method for the doped materials. Our research indicates that the Sr<sub>3</sub>Sn<sub>2</sub>P<sub>4</sub> band gap can be lowered from 1.65 to 1.0 eV by doping Eu<sup>3+</sup>. According to first-principles calculations, bands at the Fermi level are hybridised with Sr-d, Sn-p and P-p orbitals. Eu<sup>3+</sup> doping enables fine-tuning of the material’s band gap, structure and optoelectronic properties of novel phosphides by expanding the material’s potential applications in the semiconductor industry. Furthermore, calculations of the transport properties using semi-classical Boltzmann theory reveal a consistent pattern of thermopower throughout the 100–800 K range, which opens the door to the potential use of these compounds as low-temperature thermoelectric materials. ZT calculations show that both materials have reasonably strong thermoelectric performance, with just a slight fluctuation (0.18) in the results throughout a wide temperature range. Additionally, a thorough examination of the transport properties indicates that the current series of materials is p-type semiconducting. Computational studies of optoelectronic and transport properties of energy-renewable devices allow experimentalists to explore novel uses for quick and atomic-level accuracy prediction of photovoltaic materials with diverse crystal structures.</p></div>","PeriodicalId":743,"journal":{"name":"Pramana","volume":"99 3","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145169255","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}

引用次数: 0

Stability analysis of the solitary wave interaction via Lyapunov function and Hirota bilinear method 用Lyapunov函数和Hirota双线性方法分析孤立波相互作用的稳定性

IF 2.1 4区物理与天体物理

Pramana Pub Date : 2025-07-25 DOI: 10.1007/s12043-025-02960-1

N Hemnath, Santanu Raut, Sandip Saha, Awani Bhushan

{"title":"Stability analysis of the solitary wave interaction via Lyapunov function and Hirota bilinear method","authors":"N Hemnath, Santanu Raut, Sandip Saha, Awani Bhushan","doi":"10.1007/s12043-025-02960-1","DOIUrl":"10.1007/s12043-025-02960-1","url":null,"abstract":"<div><p>This study provides a comprehensive analytical and graphical exploration of the solitary wave solutions to the (3<span>(+)</span>1)-dimensional Mikhailov–Novikov–Wang integrable (MNWI) equation. We thoroughly examine the solitary wave solutions, emphasising their nonlinear wave propagation, invariant shape and constant velocity. The MNWI equation is used to derive various analytical solutions, including soliton, periodic and rational wave solutions. Additionally, we obtain a heuristic solution for the (<span>(3+1)</span>)-dimensional MNWI equation using the Hirota bilinear method, focussing on soliton wave dynamics. The analysis highlights both the mathematical framework and the physical implications of the solutions. By defining bounds on the system’s variables, we assess the overall stability through the Lyapunov function. Nonlinear wave propagation is shown to maintain stability, shape and velocity under bounded conditions. These findings confirm the essential properties and dynamics of solitons. Furthermore, the study reveals complex hybrid solutions through which wave interactions are studied. The outcomes of this work hold significant potential for modelling various physical and environmental phenomena, such as floods, tsunamis and large-scale fluid flows.\u0000</p></div>","PeriodicalId":743,"journal":{"name":"Pramana","volume":"99 3","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145169814","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}

引用次数: 0

Reducing Lax pairs to obtain integrable matrix modified Korteweg–de Vries models 简化Lax对得到可积矩阵修正Korteweg-de Vries模型

IF 2.1 4区物理与天体物理

Pramana Pub Date : 2025-07-23 DOI: 10.1007/s12043-025-02968-7

Wen-Xiu Ma

引用次数: 0

Computational and numerical analysis of the soliton solutions to the geophysical KdV equation using two robust analytical methods 用两种鲁棒分析方法计算和数值分析地球物理KdV方程的孤子解

IF 2.1 4区物理与天体物理

Pramana Pub Date : 2025-07-18 DOI: 10.1007/s12043-025-02971-y

Sidheswar Behera

{"title":"Computational and numerical analysis of the soliton solutions to the geophysical KdV equation using two robust analytical methods","authors":"Sidheswar Behera","doi":"10.1007/s12043-025-02971-y","DOIUrl":"10.1007/s12043-025-02971-y","url":null,"abstract":"<div><p>This paper investigates the soliton dynamics of the geophysical Korteweg–de Vries (GKdV) equation, focussing specifically on different types of soliton solutions that emerge within its framework: trigonometric, hyperbolic and rational solutions. Specifically, the study aims to examine elementary tsunami patterns such as rough waves, singular solitonic waves, periodic waves, sinusoidal waves and kink patterns. The coastal regions have experienced extensive urbanisation and rapid population growth, driven by the advancements of global economy. Consequently, this region is particularly susceptible to severe damages from a range of natural disasters, with tsunamis posing a significant threat. This vulnerability is evident by the occurrence of several devastating tsunami events in the 21st century, which have highlighted the exposure of certain regions to such catastrophic events. In this study, both the first integral method and the sub-ODE method are thoroughly discussed and applied to the GKdV equation. These techniques are employed to derive and analyse exact solutions, providing a deeper understanding of the behaviour and dynamics of the equation in geophysical contexts. The obtained results will enrich the understanding of the dynamics of tsunami models and provide deep insights into the propagation of nonlinear tsunami waves. The Coriolis parameter and the velocity of the travelling wave are considered to have a significant impact on tsunami waves. This study further enhances the understanding of nonlinear wave properties in a geophysical context by integrating phase portrait analysis, waveform characteristics and stability evaluations.</p></div>","PeriodicalId":743,"journal":{"name":"Pramana","volume":"99 3","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145166406","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}

引用次数: 0

On the invariant analysis and integrability of the time-fractional potential KdV equation 时间分数阶位KdV方程的不变分析与可积性

IF 2.1 4区物理与天体物理

Pramana Pub Date : 2025-07-16 DOI: 10.1007/s12043-025-02948-x

Aneeqa Ihsan, Akhtar Hussain, A. H. Kara, F. D. Zaman

引用次数: 0

Investigating the spectral statistics of (3_1^ - ) levels using random matrix theory in the odd–odd nuclei 利用随机矩阵理论研究奇-奇核中(3_1^ - )能级的谱统计

IF 2.1 4区物理与天体物理

Pramana Pub Date : 2025-07-16 DOI: 10.1007/s12043-025-02958-9

M Sayedi, H Sabri

{"title":"Investigating the spectral statistics of (3_1^ - ) levels using random matrix theory in the odd–odd nuclei","authors":"M Sayedi, H Sabri","doi":"10.1007/s12043-025-02958-9","DOIUrl":"10.1007/s12043-025-02958-9","url":null,"abstract":"<div><p>In this paper, the spectral statistics of all the observed <span>(3_1^ - )</span> levels in the odd–odd nuclei have been analysed in the framework of random matrix theory. Also, the possible effects of the shell model configurations, mass regions, theoretical quadrupole deformation, experimental half-lives and major decay modes on the statistical situations related to negative parity states have been studied. In order to prepare different sequences, we have used the latest available empirical data on the <span>(10 le A le 250)</span> mass region for 216 nuclei. Using the maximum likelihood estimation technique, the parameter of the Berry–Robnik distribution function in different sequences has been extracted and the statistical situation of these sequences in comparison with regular and chaotic limits is described. Our results show the maximum chaoticity for these odd–odd nuclei in <span>(100< A < 150)</span> mass region, short-lived nuclei. These odd–odd nuclei have the maximum theoretical quadrupole deformations. Also, there are some suggestions on the effect of shell model configuration and decay modes on the statistical situation of these negative parity states in odd–odd nuclei.</p></div>","PeriodicalId":743,"journal":{"name":"Pramana","volume":"99 3","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145165798","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}

引用次数: 0

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