Journal of Computational Electronics最新文献

{"title":"Type-II band alignment and interlayer excitons in ZnTe/TlSe van der Waals heterostructure from GW + BSE calculations","authors":"Saeid Ziksari,&nbsp;Hosein Alavi-Rad,&nbsp;Azadeh Kiani-Sarkaleh","doi":"10.1007/s10825-026-02600-w","DOIUrl":"10.1007/s10825-026-02600-w","url":null,"abstract":"<div><p>In this work, we employ first-principles calculations based on density functional theory (DFT) and many-body perturbation theory (MBPT) to investigate the structural, electronic, optical, and excitonic properties of a ZnTe/TlSe van der Waals (vdW) heterostructure, along with its constituent ZnTe and TlSe monolayers. Quasiparticle corrections obtained within the GW approximation reveal that the ZnTe and TlSe monolayers have direct and indirect band gaps of 3.02 eV and 1.67 eV, respectively, with corresponding exciton binding energies of 0.57 eV and 0.50 eV. The small lattice mismatch of 1.6% between the two monolayers enables the formation of a structurally stable ZnTe/TlSe heterostructure with minimal interface strain. The resulting heterostructure exhibits a direct quasiparticle band gap of 1.20 eV and a type-II band alignment, which facilitates efficient charge separation. The inclusion of electron–hole interactions through the Bethe–Salpeter equation (BSE) results in an optical gap of 1.02 eV and a reduced exciton binding energy of 0.18 eV. The lowest energy exciton in this heterostructure is identified as an interlayer exciton, originating from spatially separated electrons and holes residing in the TlSe and ZnTe layers, respectively. The combination of a small optical gap, moderate exciton binding energy, and multiple bright excitonic resonances across the visible and near-infrared spectral range highlights the ZnTe/TlSe vdW heterostructure as a promising candidate for next-generation photovoltaic and optoelectronic applications.</p></div>","PeriodicalId":620,"journal":{"name":"Journal of Computational Electronics","volume":"25 4","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Finite element thermoelectric assessment of LiTaO3-based pyroelectric MEMS detectors: impact of electrode materials and structural design variations","authors":"Aditi Joshi,&nbsp;Pankaj B. Agarwal","doi":"10.1007/s10825-026-02606-4","DOIUrl":"10.1007/s10825-026-02606-4","url":null,"abstract":"<div><p>This work investigates the influence of structural and material parameters on the performance of lithium tantalate (LiTaO₃)-based pyroelectric detectors using finite-element simulations. Reducing the thickness of the silicon (Si) diaphragm (underneath the pyroelectric element) from 320 to 10 μm significantly improves the detector’s thermal isolation. This leads to a reduction in the thermal time constant (<i>τ</i>) from 94 to 35 ms, increase in the current responsivity (<i>R</i>_i) from 0.5670 to 1.686 μA/W, decrease in noise equivalent power (NEP) from 4.32 × 10^–9 to 1.57 × 10^–9 W/√Hz and increase of specific detectivity (<i>D</i>^*) from 4.63 × 10⁵ to 1.27 × 10⁶ m√Hz/W. After examining the effect of different electrode materials (Au, Pt, Mo, Pd, and Al) Au and Pt were found to perform comparatively better, with <i>R</i>_i values of ~ 3.34 and 3.36 μA/W and <i>D</i>* values of 1.36 × 10⁶ and 1.37 × 10⁶ m√Hz/W, respectively. Further improvements are achieved by reducing the LiTaO₃ thickness from 100 to 5 μm, resulting in lower thermal time constants (~ 21 ms) and an increased <i>R</i>_i (up to ~ 7.3 μA/W). Although Au offers a slightly better thermal response at reduced active-layer thicknesses, it was chosen as the electrode material primarily for its ease of patterning and compatibility with standard microfabrication processes compared to Pt. Finally, variations in top electrode thickness from 150 to 50 nm, minimizes the detector thermal mass, which improves thermal time constant from 60 to 47 ms.</p></div>","PeriodicalId":620,"journal":{"name":"Journal of Computational Electronics","volume":"25 4","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466067","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analytical investigation of electric power in 3D bifacial polycrystalline silicon solar cells: impact of grain size and microstructural insights via digital microscopy","authors":"Gökhan Şahin","doi":"10.1007/s10825-026-02593-6","DOIUrl":"10.1007/s10825-026-02593-6","url":null,"abstract":"<div><p>This study presents a three-dimensional analytical model to evaluate the electrical performance of bifacial polycrystalline silicon solar cells, focusing on the effects of grain size and surface recombination velocities (Sf, Sb, Sgb). The continuity equation for minority carriers is solved using the method of separation of variables to derive closed-form expressions for excess carrier density, photocurrent, photovoltage, <i>I</i>–<i>V</i> characteristics, and power output. Power is expressed as a function of Sf, and the maximum power point (Pm) is determined through graphical analysis. Microstructural parameters such as grain size and grain boundary density obtained via digital microscopy are directly integrated into the model through their impact on grain boundary recombination velocity (Sgb). Additionally, frit thickness and uniformity are incorporated by adjusting the rear surface recombination velocity (Sb). Simulation results show that increasing grain size significantly improves carrier lifetime, photovoltage, and power output, particularly under both-sided illumination. Compared to traditional numerical approaches, the proposed analytical model offers lower computational cost and seamless integration of microscopy data, enabling rapid parametric optimization. This modeling microscopy framework provides a robust and scalable tool for the industrial optimization of high-efficiency bifacial polycrystalline silicon solar cells.</p></div>","PeriodicalId":620,"journal":{"name":"Journal of Computational Electronics","volume":"25 4","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148465822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-sensitivity dual-mode hemoglobin and chemical detection using a machine-learning-assisted bismuth–graphene THz sensor","authors":"S. Vaishnavi,&nbsp;K. Maharajan,&nbsp;C. Sheeja Herobin Rani,&nbsp;D. Jessintha,&nbsp;Manjunathan Alagarsamy","doi":"10.1007/s10825-026-02601-9","DOIUrl":"10.1007/s10825-026-02601-9","url":null,"abstract":"<div><p>This paper presents a sensor featuring a hybrid bismuth–graphene architecture optimized for simultaneous hemoglobin and chemical detection. Electromagnetic simulation using COMSOL Multiphysics demonstrates the robustness of the proposed sensor’s sensing capability across the 0.1–0.7 THz frequency bandwidth. It also shows that this sensor has high refractive-index peak sensitivity with 200 GHz/RIU for detecting hemoglobin at refractive indices from 1.34 to 1.43 and 500 GHz/RIU for detecting chemicals (analytes) at refractive indices from 1.33 to 1.366. In order to increase both the quality of the data interpretation and the predictability of results, multiple machine learning algorithms (Neural Networks, Gradient Boosting, Random Forest, Support Vector Regression) have been applied to analyze sensor data. These data-driven approaches significantly enhance analytical performance, yielding prediction accuracies above 98%, with coefficients of determination of <i>R</i>² = 0.987 for hemoglobin sensing and <i>R</i>² = 0.983 for chemical detection. Feature importance analysis reveals that resonance-frequency shift and sensitivity contribute over 60% to the model’s decision-making process. The sensor demonstrates excellent angular stability (0°–80° incidence), robust noise resilience (maintaining &gt; 90% accuracy at 10 dB SNR), and consistent cross-validation performance (standard deviation &lt; 0.02). The compact planar architecture, rapid resonance-based spectral interrogation, and machine-learning-assisted prediction enable near real-time analyte estimation while maintaining compatibility with integrated terahertz source–detector and microfluidic platforms. These characteristics position the proposed sensor as a promising design for portable biomedical diagnostics and environmental monitoring applications, combining high sensitivity with intelligent data-driven signal interpretation.</p></div>","PeriodicalId":620,"journal":{"name":"Journal of Computational Electronics","volume":"25 4","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148465317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design of xanthenone-based photoactive chromophores with peripheral acceptor moieties for promising photovoltaic properties","authors":"Iqra Shafiq,&nbsp;Ayesha Mussarat,&nbsp;Rabia Baby,&nbsp;Aiman Jabbar,&nbsp;Khurram Shahzad Munawar,&nbsp;Muhammad Haroon,&nbsp;Norah Alhokbany","doi":"10.1007/s10825-026-02559-8","DOIUrl":"10.1007/s10825-026-02559-8","url":null,"abstract":"<div><p>We propose a series of derivatives (HDXR–HDX7) using the xanthenone-based photoactive compound (HDX) by introducing various electron-withdrawing groups at its terminal acceptors, emphasizing their potential as photovoltaic materials. Density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations were employed using the M06 functional along with the 6-311G(d,p) basis set to investigate the optoelectronic and photovoltaic properties of these compounds. The frontier molecular orbitals (FMOs) revealed their energy gap in the range of 2.859−3.378 eV with the following trend: HDX4 &lt; HDX3 &lt; HDX6 &lt; HDX5 &lt; HDX7 &lt;HDX2 &lt; HDX1 &lt; HDXR. The global reactivity parameters (GRPs) calculated through highest occupied molecular orbital (HOMO)/lowest unoccupied molecular orbital (LUMO) energies illustrated higher softness with reduced hardness values. All designed derivatives exhibited redshifted absorption spectra (446.903–516.407 nm) in comparison with HDXR (444.276 nm) and revealed enhanced light-harvesting efficiency. Moreover, the density of states (DOS) plots showed significant transfer of charges between HOMO and LUMO. The lower binding energy (<i>E</i>_b) values (0.458–0.594 eV) exhibited higher exciton dissociation strength, which also supported their transition density matrix (TDM) maps. Among all the designed derivatives, HDX4 showed the most suitable results for solar cells, with a minimal energy gap of 2.859 eV and <i>E</i>_b = 0.458 eV along with the highest bathochromic shift (<i>λ</i>_max = 516.407 nm). The photovoltaic properties, in particular the open-circuit voltage (<i>V</i>_oc), were calculated with respect to the <b>PBDB-T</b> donor, and comparable results were obtained for all the investigated chromophores. Thus, the results indicate that the proposed xanthenone-based chromophores are good candidate materials for use in photovoltaic applications.</p></div>","PeriodicalId":620,"journal":{"name":"Journal of Computational Electronics","volume":"25 4","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148465511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-Q and low-detection-limit one-dimensional photonic crystal sensor for edible oil adulteration","authors":"Sanjeev K. Srivastava,&nbsp;Vipin Kumar,&nbsp; Anjali,&nbsp;Sanjeev Sharma","doi":"10.1007/s10825-026-02603-7","DOIUrl":"10.1007/s10825-026-02603-7","url":null,"abstract":"<div><p>This work presents the theoretical investigation of a one-dimensional defective photonic crystal structure proposed for edible oil impurity detection.The structure consists of alternating MgF₂ and TiO₂ layers with different oil mixtures introduced as the defect layer. Mustard oil is considered as the base oil, while argemone oil, rice bran oil, and palm oil are treated as impurity oils. The transmission characteristics of the proposed structure are investigated using the Transfer Matrix Method (TMM). The results show that the defect mode wavelength shifts systematically with changes in impurity concentration and refractive index. The effect of periodic layers and defect layer thickness on sensor performance is also analyzed. The proposed sensor exhibits high transmittance, narrow resonance linewidth, high quality factor, and excellent figure of merit. A sensitivity of nearly 298–299 nm/RIU, Q-factor- 3.6 × 10⁵, figure of merit (FOM) 6.0 × 10⁴ (RIU⁻¹) and a detection limit of 1.64 × 10^–6 RIU are achieved, indicating the excellent sensing capability of the proposed structure for edible oil quality monitoring applications.</p></div>","PeriodicalId":620,"journal":{"name":"Journal of Computational Electronics","volume":"25 4","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148465205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of retention characteristic improvement in reprogram process based on a physical model for 3D NAND flash memory","authors":"Jooyoung Lee,&nbsp;Hyungcheol Shin","doi":"10.1007/s10825-026-02599-0","DOIUrl":"10.1007/s10825-026-02599-0","url":null,"abstract":"<div><p>This study investigates the improvement in retention characteristic in the reprogram scheme of 3D NAND Flash memory using a physical model. The silicon-oxide-nitride-oxide-silicon (SONOS) structure is employed, and the charge-trap layer (CTL) is analyzed according to trap levels. Traps inside the CTL are categorized into shallow trap levels (STL) and deep trap levels (DTL), with multiple levels sampled according to the distribution of trap concentration as a function of trap depth. Charge loss during the reprogram interval is analytically calculated based on electron emission, and the relative contributions of shallow and deep traps are compared after the second program operation. The results demonstrate that the electron trap distribution shifts toward a higher DTL concentration compared with the one-shot program. Furthermore, a trade-off relationship is proposed, in which retention characteristic can be tuned by adjusting the interval time between two program operations. The results were calibrated against measurement data and validated with technology computer-aided design (TCAD) simulations, and a voltage biasing scheme is proposed to enhance reliability.</p></div>","PeriodicalId":620,"journal":{"name":"Journal of Computational Electronics","volume":"25 4","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10825-026-02599-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148465204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design and computational analysis of black phosphorus-based D-shaped PCF-SPR refractive index sensor","authors":"Nidhi Yadav,&nbsp;Akash Khamaru,&nbsp;Deepak Garg,&nbsp;Ajeet Kumar","doi":"10.1007/s10825-026-02595-4","DOIUrl":"10.1007/s10825-026-02595-4","url":null,"abstract":"<div><p>Recently, plasmonic photonic crystal fiber (PCF)-based refractive index sensors have drawn interest for their high sensitivity and capability to perform label-free, real-time detection. Therefore, this paper describes the design and functionality of a new D-shaped PCF biosensor combined with black phosphorus (BP)–gold and Ta₂O₅ layers for refractive index sensing and early detection of anemia. To achieve light confinement in PCF, this design includes two kinds of air holes: elliptical and circular. The proposed sensor is coated with a layer of gold and a Ta₂O₅ adhesion layer, which serves a dual purpose by enhancing the plasmonic response while simultaneously providing adhesion between the PCF and the gold coating. Additionally, 17 layers of BP—a growing 2D plasmonic material—are also layered on the gold + Ta₂O₅ layer to enhance sensitivity, which has a monolayer thickness of 0.53 nm. The proposed sensor is used to detect a wide range of RI ranging from 1.31 to 1.38. After incorporating BP layers, the dynamic sensitivity of developed sensor enhanced from 5500 to 12,000 nm/RIU. The BP-layered hybrid sensor achieved amplitude sensitivity of − 252.28 RIU⁻¹. The proposed structure is numerically analyzed with the finite element method (FEM) in COMSOL Multiphysics. Furthermore, the optimized structure achieved wavelength sensitivity of 5500 nm/RIU at 140 g/L for the gold-coated PCF sensor and 14,500 nm/RIU at 140 g/L for BP–gold-coated PCF sensor for anemia detection. Therefore, the suggested PCF-SPR biosensor based on black phosphorus could be useful for the early diagnosis of anemia.</p></div>","PeriodicalId":620,"journal":{"name":"Journal of Computational Electronics","volume":"25 4","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148465340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phase accumulation for machine learning readout in graphene terahertz resonators","authors":"Álvaro Garay","doi":"10.1007/s10825-026-02597-2","DOIUrl":"10.1007/s10825-026-02597-2","url":null,"abstract":"<div><p>This work presents a phase-accumulation-based machine learning readout for dynamically perturbed graphene terahertz resonators. Instead of relying on steady-state or peak-only observables, the proposed approach integrates the transient phase response to construct physically meaningful features that capture both perturbation magnitude and temporal behavior. A physics-driven synthetic dataset is generated using a reduced-order dynamic model, incorporating parameter variability and noise. Multiple feature configurations are evaluated for classification and regression tasks. The results show that accumulated-phase descriptors alone are insufficient, but significantly improve performance when combined with instantaneous features, leading to enhanced robustness and predictive accuracy, particularly under low signal-to-noise conditions. The proposed framework provides a physics-informed pathway for integrating machine learning into graphene-based terahertz sensing systems.</p></div>","PeriodicalId":620,"journal":{"name":"Journal of Computational Electronics","volume":"25 4","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148465064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An FDTD-TDDFT method for the EM/QM co-simulation of nanowire systems in the Lorenz gauge","authors":"Maxim Torreele,&nbsp;Emile Vanderstraeten,&nbsp;Dries Vande Ginste","doi":"10.1007/s10825-026-02570-z","DOIUrl":"10.1007/s10825-026-02570-z","url":null,"abstract":"<div><p>Real-time time-dependent density functional theory (TDDFT) constitutes a cornerstone in the modeling of nanoscale materials. Although numerous application areas have already benefited from the technique, investigation of both forward and backward coupling in matter systems subject to a vectorial electromagnetic (EM) perturbation remains challenging. To address this problem, this work proposes a modeling framework leveraging the finite-difference time-domain algorithm for determining the scalar and vector potential from the EM fields, both in the traditional Coulomb gauge as well as the nearly unexplored Lorenz gauge. Using the latter allows for a straightforward calculation of the electromagnetic vector potential, a natural implementation of perfectly matched layers, and a significant reduction in computation time. To describe the pertaining quantum-mechanical (QM) dynamics, a real-space and full-potential formulation of TDDFT has been utilized. Furthermore, a multistep algorithm is leveraged to bridge the gap between the stability limits of the EM and QM subsystems. The method is applied to practical nanowire topologies to demonstrate its versatility. The results exhibit an excellent correspondence between both gauges, while highlighting the superior numerical performance of the Lorenz gauge technique.</p></div>","PeriodicalId":620,"journal":{"name":"Journal of Computational Electronics","volume":"25 4","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148465062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}