IF 3.1 3区物理与天体物理

Optik Pub Date : 2026-04-01 Epub Date: 2026-01-12 DOI: 10.1016/j.ijleo.2026.172671

P. Sushma Chowdary , V.Vijayasri Bolisetty , U. Yedukondalu , Bokkisam Venkata Sai Sailaja

{"title":"Performance evaluation of multi band disk-shaped terahertz MIMO antenna with hexagon slots on ground for future 6 G and terahertz communication system","authors":"P. Sushma Chowdary , V.Vijayasri Bolisetty , U. Yedukondalu , Bokkisam Venkata Sai Sailaja","doi":"10.1016/j.ijleo.2026.172671","DOIUrl":"10.1016/j.ijleo.2026.172671","url":null,"abstract":"<div><div>In this paper, a four-port wideband MIMO antenna is developed for future 6 G wireless communication systems. The proposed disk-shaped antenna consists of four identical disk-shaped elements arranged uniformly around a circular structure. This uniform arrangement helps maintain geometric balance and minimizes mutual coupling. All the disk patterns are arranged equidistantly around the centrally etched flower-like structure, which ensures the symmetrical geometry of the proposed antenna. These slots are helpful in generating a super-wide bandwidth ranging from 1.81 THz to 4.1513 THz. To further enhance the efficiency of the antenna, hexagonal slots are etched on the ground plane. The hexagonally etched slots on the ground reduce signal reflection losses. The overall dimensions of the four-port MIMO antenna are 800 × 800 × 50 µm³ , and it is designed on a silicon substrate with a relative permittivity of 11.9. The proposed antenna achieves a super-wide bandwidth ranging from 0.926 THz to 5.5411 THz and a peak gain of 7 dB. MIMO performance parameters such as diversity gain, Total Active Reflection Coefficient (TARC), Envelope Correlation Coefficient (ECC), and Channel Capacity Loss (CCL) are evaluated, and all lie within acceptable ranges. The disk-shaped antenna demonstrates super-wideband characteristics, high resolution, and a low reflection coefficient. The disk-shaped antenna operates at 1.8175 THz, 2.5911 THz, 3.286 THz, and 4.1513 THz, with reflection coefficients of −28.02 dB, −35.723 dB, −37.11 dB, and −32.35 dB, respectively. Considering to its compact size, wide bandwidth, and stable radiation characteristics, the proposed disk-shaped antenna is well suited for high-speed THz communication and beyond-6G wireless applications.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"347 ","pages":"Article 172671"},"PeriodicalIF":3.1,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145978582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Antibunching and sub-Poissonian photon statistics in degenerate frequency up-conversion process 简并频率上转换过程中的反聚束和亚泊松光子统计

IF 3.1 3区物理与天体物理

Optik Pub Date : 2026-04-01 Epub Date: 2026-01-07 DOI: 10.1016/j.ijleo.2026.172668

Rupesh Singh , Dilip Kumar Giri

{"title":"Antibunching and sub-Poissonian photon statistics in degenerate frequency up-conversion process","authors":"Rupesh Singh , Dilip Kumar Giri","doi":"10.1016/j.ijleo.2026.172668","DOIUrl":"10.1016/j.ijleo.2026.172668","url":null,"abstract":"<div><div>The work is devoted to the antibunching and sub-Poissonian photon statistics in the degenerate frequency up-conversion (FUC) process using a short-time approximation in the Heisenberg picture. We analyse how pump photon numbers, interaction times, and coupling strengths affect nonclassicality, distinguishing between first- and second-order Hamiltonian interactions. Results show that first-order interactions lead to stronger nonclassical effects, though only second-order interactions enable antibunching in the harmonic mode due to higher-order pump contributions. Photon antibunching intensity increases with pump strength and shorter interaction times. In the first-order coupling interactions, the harmonic mode does not exhibit antibunching because a coherent or vacuum pump induces photon clustering. However, second-order interactions, where higher powers of the pump field contribute significantly, facilitate antibunching in the harmonic mode. Third-order antibunching exhibits the strongest nonclassical behaviour within the observed effects, followed by second- and first-order antibunching. It is more apparent that increased pump intensity and reduced interaction time both strengthen antibunching and sub-Poissonian photon statistics. While the pump mode exhibits clear antibunching, the harmonic mode displays milder nonclassicality. These results reveal the higher-order transitions of antibunching as an inherent quantum feature of light, valuable for quantum communication and single-photon sources with a probabilistic destination.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"347 ","pages":"Article 172668"},"PeriodicalIF":3.1,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145978585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Evaluating short term financial marketing bitcoin prediction: A comparative analysis of large-kernel attention graph convolutional networks across various prediction horizon 评估短期金融营销比特币预测：跨不同预测范围的大核注意图卷积网络的比较分析

IF 3.1 3区物理与天体物理

Optik Pub Date : 2026-04-01 Epub Date: 2025-12-29 DOI: 10.1016/j.ijleo.2025.172663

Mohideen AbdulKader M , Sudhansu Sekhar Nanda , K. Sampath , D. Barani

{"title":"Evaluating short term financial marketing bitcoin prediction: A comparative analysis of large-kernel attention graph convolutional networks across various prediction horizon","authors":"Mohideen AbdulKader M , Sudhansu Sekhar Nanda , K. Sampath , D. Barani","doi":"10.1016/j.ijleo.2025.172663","DOIUrl":"10.1016/j.ijleo.2025.172663","url":null,"abstract":"<div><div>One of the most popular investment assets nowadays is Bitcoin. The financial market volatility of bitcoin's price has drawn the attention of researchers and investors alike to the ways in which its price fluctuates. The paper proposes an evaluation of Short Term Financial Marketing Bitcoin Prediction: A Comparative Analysis of Large-Kernel Attention Graph Convolutional Networks across Various Prediction Horizons (BP-ST-LAGCN-NOA) for short-term Bitcoin market prediction. Then, pre-processed data are fed to the Large-kernel Attention Graph Convolutional Network (LAGCN) to effectively predict the bitcoin market in the short term. LAGCN does not express adaptive optimization strategies to determine optimal factors to effectively predict the Bitcoin market. Hence, the Nutcracker Optimization Algorithm (NOA) is employed to optimize the weight parameter of the Large-kernel Attention Graph Convolutional Network to predict the bitcoin market. Then the proposed BP-ST-LAGCN-NOA is implemented in Python, and the performance metrics like Accuracy, Precision, Recall, Specificity, F1-score, and ROC are analysed. The BP-ST-LAGCN-NOA model achieves 99.64 % accuracy, 99.21 % precision, 99.18 % recall, 98.14 % F1-Score and 98.47 % specificity, outperforming all baseline methods. The BP-ST-LAGCN-NOA model demonstrates superior accuracy and robustness in short-term Bitcoin market prediction, outperforming existing machine learning (ML) and deep learning (DL) approaches.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"347 ","pages":"Article 172663"},"PeriodicalIF":3.1,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145927522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Dual-parameter tunable high-Q optical response in 1D photonic crystals with Kerr-nonlinear graphene and polymer defect layers 具有克尔非线性石墨烯和聚合物缺陷层的一维光子晶体的双参数可调谐高q光响应

IF 3.1 3区物理与天体物理

Optik Pub Date : 2026-04-01 Epub Date: 2026-01-09 DOI: 10.1016/j.ijleo.2026.172670

Oumayma Habli , Jihene Zaghdoudi , Mounir Kanzari

引用次数: 0

Numerical and experimental characterization of whispering gallery modes in a microcylinder for displacement and force sensing 位移和力传感用微柱低语通道模态的数值和实验表征

IF 3.1 3区物理与天体物理

Optik Pub Date : 2026-03-01 Epub Date: 2025-11-20 DOI: 10.1016/j.ijleo.2025.172606

Mahdi Shayganmanesh, Mohammad Hossein Mahdieh, Reyhane Mokhtari

{"title":"Numerical and experimental characterization of whispering gallery modes in a microcylinder for displacement and force sensing","authors":"Mahdi Shayganmanesh, Mohammad Hossein Mahdieh, Reyhane Mokhtari","doi":"10.1016/j.ijleo.2025.172606","DOIUrl":"10.1016/j.ijleo.2025.172606","url":null,"abstract":"<div><div>In this paper a microcylindrical resonator sensor was fabricated using PDMS polymer. The sensor works based on whispering gallery mode (WGM). The microcylinder filled with solution of Rhodamine 6B and glycerol. The Rhodamine was optically pumped by the second harmonics of a pulsed Nd:YAG laser beam and its emission provided WGM and resonance in microcylinder. The WGM spectra of microcylinder under applied forces were detected and analyzed by using a spectrophotometer. In addition to WGM spectra, optical images of the microcylinder under applied forces were taken using an appropriate optical set up and employing a CCD camera. The optical images show that any force on microcylinder side modifies its cross section from micro disk to micro elliptic. The experimental results show that such deformation in cross section leads to blue shift in WGM resonance wavelength. Using the geometrical data of images and a simple theory, the blue shifts due to force were estimated by calculations. The numerical results show good agreement with the experimental results.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"346 ","pages":"Article 172606"},"PeriodicalIF":3.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145584388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Securing iris image templates through ECC-based phase retrieval mask and multi-domain transforms integrated with chaotic umbrella mapping 基于相位检索掩模和混沌伞映射的多域变换对虹膜图像模板的保护

IF 3.1 3区物理与天体物理

Optik Pub Date : 2026-03-01 Epub Date: 2025-11-20 DOI: 10.1016/j.ijleo.2025.172605

Bhavana Sharma , Pankaj Rakheja , Hukum Singh , Mehak Khurana

{"title":"Securing iris image templates through ECC-based phase retrieval mask and multi-domain transforms integrated with chaotic umbrella mapping","authors":"Bhavana Sharma , Pankaj Rakheja , Hukum Singh , Mehak Khurana","doi":"10.1016/j.ijleo.2025.172605","DOIUrl":"10.1016/j.ijleo.2025.172605","url":null,"abstract":"<div><div>The increasing demand of biometric technology in various applications highlights the important role of iris image templates encryption in ensuring robust image security safeguarding the confidentiality, legitimacy, and authenticity of iris images. This paper presents a novel encryption technique designed to improve security of iris image templates. The proposed technique combines elliptic curve cryptography (ECC), chaotic umbrella maps, and an uneven modulus decomposition (UMD) algorithm. The Gyrator and fractional Fourier domains are jointly leveraged for their non-linear transformation characteristics, enhancing encryption complexity. The Umbrella Map is incorporated along with phase masks produced by elliptic curve cryptography to strengthen the security. To add an extra layer of security, pixel scrambling is also introduced, enabling the conversion of iris input images into a one-channel encrypted output. MATLAB simulations and security tests were carried out, including statistical analysis, critical sensitivity assessments, and a look at possible threats. The outcomes demonstrate the scheme's resistance to statistical inspection, important sensitivity analysis, and noise attacks. The robust encryption method ensures protection against known, specific, and plaintext assaults.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"346 ","pages":"Article 172605"},"PeriodicalIF":3.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145584481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

An intelligent adaptive hybrid learning-based detection framework to evade DDoS attack for secure virtualized infrastructures in cloud computing environment 针对云计算环境下安全的虚拟化基础设施，提出了一种基于智能自适应混合学习的DDoS攻击检测框架

IF 3.1 3区物理与天体物理

Optik Pub Date : 2026-03-01 Epub Date: 2025-12-12 DOI: 10.1016/j.ijleo.2025.172641

Chinnala Balakrishna , Sanaboina Leela Krishna , Sridhar Mourya , B. Giridhar , Chaluvadi V. Raghavendran , Sudha Singaraju

{"title":"An intelligent adaptive hybrid learning-based detection framework to evade DDoS attack for secure virtualized infrastructures in cloud computing environment","authors":"Chinnala Balakrishna , Sanaboina Leela Krishna , Sridhar Mourya , B. Giridhar , Chaluvadi V. Raghavendran , Sudha Singaraju","doi":"10.1016/j.ijleo.2025.172641","DOIUrl":"10.1016/j.ijleo.2025.172641","url":null,"abstract":"<div><div>“Cloud computing has transformed technology” with its unmatched scalability and ease of access, allowing users to leverage services under a flexible pay-as-you-go model. Distributed Denial of Service (DDoS) attacks hijack many distributed devices to overwhelm systems, making them a persistent cybersecurity concern. Although there are various detection methods already, the growing complexity and frequency of these threats demand more resilient and adaptive security solutions. Existing detection methods frequently fall short in effectively handling the dynamic nature of cloud environments. These limitations collectively motivate the development of more robust and integrated approaches. As a result, this study presents a new architecture for detecting DDoS attacks in virtual cloud computing systems using the Adaptive Hybrid Learning (AHyL) approach. Initially, datasets are collected from publicly available standard sources. Then, the gathered data undergoes data preprocessing to improve its quality. Subsequently, a Spatial Cross-Attention-based Fuzzy Autoencoder (SCA-FAE) is employed to extract robust features. The combination of Spatial Cross-Attention (SCA) and Fuzzy Autoencoder (FAE) in the SCA-FAE approach offers the distinctive advantage by leveraging spatial correlations and handling data uncertainty. These extracted features are forwarded to the AHyL model for the detection process. This offers the distinctive advantage of integrating an Extreme Learning Machine (ELM) with a Residual Recurrent Neural Network (Res-RNN) to balance high-speed processing. Prediction performance is further enhanced by optimizing the model’s parameters using the Random Number Updated Hippopotamus Optimization (RNU-HO) algorithm. Finally, a comparative evaluation shows that the proposed technique significantly outperforms traditional approaches.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"346 ","pages":"Article 172641"},"PeriodicalIF":3.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145786603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Propagation of vector solitons in waveguides with Helmholtz resonators: Transmission-line approach 亥姆霍兹谐振器波导中矢量孤子的传播：在线传输方法

IF 3.1 3区物理与天体物理

Optik Pub Date : 2026-03-01 Epub Date: 2025-12-09 DOI: 10.1016/j.ijleo.2025.172635

Souleymanou Abbagari , Alphonse Houwe , Lanre Akinyemi , Doka Yamigno Serge , Bouetou Thomas Bouetou

{"title":"Propagation of vector solitons in waveguides with Helmholtz resonators: Transmission-line approach","authors":"Souleymanou Abbagari , Alphonse Houwe , Lanre Akinyemi , Doka Yamigno Serge , Bouetou Thomas Bouetou","doi":"10.1016/j.ijleo.2025.172635","DOIUrl":"10.1016/j.ijleo.2025.172635","url":null,"abstract":"<div><div>This paper investigates vector soliton interactions within an air-filled acoustic waveguide that is side-loaded with Helmholtz resonators and modeled as a transmission line incorporating nearest-neighbor coupling. Using a semi-discrete approximation, we derive coupled nonlinear Schrödinger equations that reveal how self-phase and cross-phase modulation depend on the normalized frequency. Analytical results indicate that only coupled bright-bright and dark-dark soliton interactions can propagate within the frequency bands supported by the resonator structure, while bright-dark and dark-bright soliton pairs are inhibited due to the influence of coupling strength. Modulation instability analysis highlights the role of nearest-neighbor coupling in altering the intensity and bandwidth of these solitons. Numerical simulations further demonstrate that the waveguide configuration supports the long-term evolution of wavenumbers, giving rise to rogue waves and periodic breathers under varying coupling conditions. Notably, the excitation of specific frequency bands allows for the emergence of Akhmediev breathers of types A and B during certain propagation intervals. In general, this study unveils novel wave dynamics introduced by incorporating nearest-neighbor coupling in acoustic waveguides with Helmholtz resonators.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"346 ","pages":"Article 172635"},"PeriodicalIF":3.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145786662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Numerical investigation of one-soliton and two-soliton collision solutions in a nonlinear ferromagnetic equation 非线性铁磁方程中单孤子和双孤子碰撞解的数值研究

IF 3.1 3区物理与天体物理

Optik Pub Date : 2026-03-01 Epub Date: 2025-12-11 DOI: 10.1016/j.ijleo.2025.172639

Indira Sundaram , J. Sivapragasam , Sathishkumar Perumal

{"title":"Numerical investigation of one-soliton and two-soliton collision solutions in a nonlinear ferromagnetic equation","authors":"Indira Sundaram , J. Sivapragasam , Sathishkumar Perumal","doi":"10.1016/j.ijleo.2025.172639","DOIUrl":"10.1016/j.ijleo.2025.172639","url":null,"abstract":"<div><div>This study presents a numerical investigation of electromagnetic (EM) soliton propagation and collision phenomena in an anisotropic ferromagnetic medium characterized by higher-order nonlinearity and dispersion. The interaction between the magnetization of the medium and the magnetic field component of the EM wave is studied by solving Maxwell’s equations coupled with the Landau-Lifshitz (L-L) equation, which governs the magnetization dynamics. The resulting nonlinear magnetization behavior is described by a generalized derivative nonlinear Schrödinger (DNLS) equation, selected for its ability to capture complex spin interactions and electromagnetically induced nonlinear effects that are inadequately represented in conventional integrable models. To investigate the nonlinear spin excitations, we perform numerical simulations by solving the generalized DNLS equation using the Method of Lines, implemented in Mathematica software. This approach enables the identification of nonlinear spin excitations in the form of damped and amplitude-modulated one-soliton structures and phase-sensitive two-soliton collisions. Despite energy dissipation, the interactions retain spatial coherence, demonstrating the robustness of solitonic behavior under dispersive and nonlinear perturbations. Dispersion plays a critical role in modulating collision timing and shaping the post-interaction profiles. These findings advance the understanding of soliton robustness under perturbative conditions and provide valuable insights into nonlinear EM wave propagation with potential applications in magneto-optic switching and soliton-based waveguide technologies.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"346 ","pages":"Article 172639"},"PeriodicalIF":3.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145786664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Electronic, transport and optical properties of a p-type transparent conductive oxides family A2B2O7 (A=Sn, Pb, B= Nb, Ta): A density functional theory study p型透明导电氧化物家族A2B2O7 （a =Sn, Pb， B= Nb, Ta）的电子、输运和光学性质：密度泛函理论研究

IF 3.1 3区物理与天体物理

Optik Pub Date : 2026-03-01 Epub Date: 2025-12-05 DOI: 10.1016/j.ijleo.2025.172634

Ting Yang , Wen-Guang Li , Zheng-Tang Liu , Qi-Jun Liu

引用次数: 0

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