In this work, a high-performance vertical photodetector using Sr3SbCl3 as the active perovskite absorber is comprehensively investigated numerically via SCAPS-1D software. The proposed photodetector is designed for broadband sensing (300–900 nm) and involves CuI as the hole transport layer and SnO2 as the electron transport layer, enhancing the charge extraction pathways. Herein, the absorber layer is subjected to a systematic optimization strategy that involves thickness tuning, total and interfacial defect densities. Here, operational conditions such as- temperature, series and shunt resistances are also varied. These engineering steps significantly improve carrier generation, suppress recombination and optimize the interfacial charge dynamics. As such, the optimized photodetector presents a photocurrent density of 27.126 mA/cm2 and immensely better optoelectronic performance with a peak responsivity of 0.588 A/W and an impressive detectivity of 8.4 × 1017 Jones at 760 nm. It further underscores the great potential of using environmentally friendly lead-free Sr3SbCl3 perovskites for high sensitivity photodetection. These insights from the optimization framework can act as guidelines for developing next-generation perovskite vertical photodetectors tailored for visible light applications in future advances in imaging, optical communication and low-light sensing technologies.
In large-scale IoT and mobile networks, broadcasting is an important method of data dissemination to present real-time information efficiently to many devices. This paper introduces a new ML-Based Adaptive Broadcast Scheduling (ML-ABS) framework. The proposed framework combines mobility prediction, zone-aware indexing, and secure indexing for data broadcasting. By using LSTM-based mobility prediction and Random Forest zone classification, the scheduler dynamically allocates bandwidth and prioritizes data dissemination based on the predicted zone density. We conducted experiments using CRAWDAD mobility datasets. The results show that the LSTM model consistently outperforms Random Forest, achieving accuracies between 89
The continuous persistence of fake news harms public trust and distorts online information ecosystems. For reliable and interpretable fake news detection, this paper proposes a lightweight hybrid deep learning model that integrates Convolutional Neural Network (CNN), Bidirectional Long Short-Term Memory (BiLSTM) networks, sentiment polarity features, and a Naïve Bayes classifier. First, the CNN–BiLSTM encodes both local and sequential textual patterns, and lexicon-based sentiment cues capture emotional signals usually carried by misinformation. Second, Naïve Bayes brings a probabilistic and robust decision layer over the fused deep and sentiment representations. Extensive experiments on two benchmark datasets, Kaggle Fake News and FakeNewsNet, in a five-fold cross-validation setting, are performed. It achieves 83.17
In this work, a novel tunable terahertz metamaterial perfect absorber (TMMPA) is proposed, composed of a 2 x 2 array of unit cells, where each cell consists of four concentric vanadium dioxide (VO2) rings patterned over a silicon dioxide (SiO2) substrate with a gold (Au) ground plane. It ensures zero transmission and contributes to high absorption efficiency. The absorber exhibits an ultra-wideband response from 2.5 THz to 9.5 THz, with absorption remaining above 90 % across this range. A near-unity absorption approaching of 100 % is achieved from 4.0 THz to 6.8 THz, while the single unit cell shows a narrower bandwidth of 5.5 THz to 6.8 THz. The fractional bandwidth of the proposed array is approximately 116.66 %, classifying it as ultrawideband in the terahertz regime. Tunability is realized by varying the conductivity of VO2 from 200 S/m (insulating state) to 2 x 105 S/m (metallic state). Further, the absorber maintains high performance for both TE and TM polarizations and demonstrates strong angular stability due to its symmetrical concentric-ring geometry. The tunability of the proposed TMMPA is achieved by dynamically varying the electrical conductivity of VO2, which undergoes a phase transition that significantly alters its electromagnetic properties under external stimuli such as temperature or electric field. The design and electromagnetic performance of the proposed absorber were analyzed and simulated using CST Microwave Studio. To further validate the physical mechanism behind the absorption behavior, an equivalent RLC circuit model was developed and simulated using Advanced Design System (ADS) software. The results obtained from the CST simulations showed excellent agreement with the corresponding RLC circuit model, confirming the accuracy and effectiveness of the proposed design methodology. The combination of ultra-wideband operation, near-unity absorption, tunability, polarization insensitivity, and angular stability makes the TMMPA highly suitable for 6G terahertz applications.
Vanadium pentoxide (V2O5) films were synthesized on glass substrates employing the screen-printing technique at sintering temperatures of 500 degrees C and 600 degrees C. The structural properties of the V2O5 films were scrutinized utilizing scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The optical characteristics were assessed through UV-Vis spectroscopy and photoluminescence (PL) spectroscopy. XRD analysis revealed an increase in crystal size concomitant with the elevation of temperature. SEM investigations disclosed increased grain sizes and diminished particle agglomeration, with the emergence of voids in various regions as the sintering temperature escalated. FTIR examination demonstrated minor shifts and more pronounced peaks at elevated temperatures. Optical absorption assessments exhibited direct band gap semiconductor behavior, with band gap energies approximating 2.10 eV for films sintered at 500 degrees C and 1.95 eV for those subjected to 600 degrees C. PL spectroscopy indicated a red shift in band emission corresponding to the rise in sintering temperature. These observations imply that elevated sintering temperatures significantly enhance the crystallinity of V2O5 films while concurrently reducing structural defects and improving crystalline quality.
