Nanotechnology最新文献

{"title":"Coupling of single nanodiamonds hosting SiV color centers to plasmonic double bowtie microantennas.","authors":"S Lindner, N Rahbany, C Pauly, L Gines, S Mandal, O A Williams, A Muzha, A Krueger, R Bachelot, C Couteau, C Becher","doi":"10.1088/1361-6528/ada9a4","DOIUrl":"10.1088/1361-6528/ada9a4","url":null,"abstract":"<p><p>Color centers are promising single-photon emitters owing to their operation at room temperature and high photostability. In particular, using nanodiamonds as a host material is of interest for sensing and metrology. Furthermore, being a solid-state system allows for incorporation to photonic systems to tune both the emission intensity and photoluminescence (PL) spectrum and therefore adapt the individual color center to desired properties. We show successful coupling of a single nanodiamond hosting silicon-vacancy color centers to a plasmonic double bowtie antenna structure. To predict the spectrum of the coupled system, the PL spectrum of the silicon vacancy centers was measured before the coupling process and convoluted with the antenna resonance spectrum. After transferring the nanodiamond to the antenna the combined spectrum was measured again. The measurement agrees well with the calculated prediction of the coupled system and therefore confirms successful coupling.</p>","PeriodicalId":19035,"journal":{"name":"Nanotechnology","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142979248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modulating the properties of g-C₃N₄through two-step annealing and ionic-liquid gating.","authors":"Na Sa, Kaiqi Nie, Yi Sheng Ng, Tielong Deng, Jinfeng Xu, Weichao Wang, Yixiao Deng, Jiaou Wang, Junyong Kang, Jin-Cheng Zheng, Meng Wu, Hui-Qiong Wang","doi":"10.1088/1361-6528/ada4b7","DOIUrl":"10.1088/1361-6528/ada4b7","url":null,"abstract":"<p><p>The graphitic carbon nitride (g-C₃N₄) is an important optoelectronic and photocatalytic material; however, its application is limited by the high recombination rate of the electron-hole (e^--h⁺) pairs. In this work, we reported a novel strategy combining two-step annealing treatment and ionic-liquid (IL) gating technology for effectively regulating the properties of g-C₃N₄, especially largely reducing the recombination rate of the e^--h⁺pairs, which is evidenced by a remarkable reduction of the photoluminescence (PL) intensity. Firstly, g-C₃N₄samples with typical layered structure were obtained by annealing melamine with temperature of 600 °C. Further annealing of the samples at 600 °C with much longer time (from 4 h to 12 h) were found to effectively reduce the imperfections or defects, and thus the PL intensity (49% reduction). This large reduction of PL intensity is attributed to the improved interconnection of triazine units, the shortened charge transfer diffusion distances, and the reduced interlayer spacing, which facilitate electron relocation on the g-C₃N₄surface. Secondly, by post-treating the annealed sample with IL, the PL intensities were found to be further reduced, mainly due to the passivation of charged defect centers by IL. Additionally, applying an external electric field in an IL environment can significantly enhance the charged defect passivation. Overall, by utilizing electric field-controlled IL gating, defect states in g-C₃N₄were passivated, leading to a significant reduction in PL intensity and an extension of PL lifetime, thereby effectively decreasing the e^--h⁺recombination rate in the material. This study demonstrates a new approach for defect passivation, providing insights and strategies for modulating properties of advanced materials such as g-C₃N₄.</p>","PeriodicalId":19035,"journal":{"name":"Nanotechnology","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142922256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancing the ferroelectric performance of Hf_0.5Zr_0.5O₂films by optimizing the incorporation of Al dopant.","authors":"Xin Liu, Weidong Zhao, Jiawei Wang, Lulu Yao, Man Ding, Yonghong Cheng","doi":"10.1088/1361-6528/adaf2c","DOIUrl":"10.1088/1361-6528/adaf2c","url":null,"abstract":"<p><p>HfO₂-based ferroelectric (FE) thin films have gained considerable interest for memory applications due to their excellent properties. However, HfO₂-based FE films face significant reliability challenges, especially the wake-up and fatigue effects, which hinder their practical application. In this work, we fabricated 13.5 nm-thick Al-doped Hf_0.5Zr_0.5O₂(HZO) films with both uniform (UD) and optimized (OD) Al distributions, systematically investigating the effects of Al doping distribution on their FE and endurance performances. After optimizing the Al distribution, the OD samples exhibit significantly enhanced ferroelectricity, with a robust remnant polarization (2<i>P</i>_r) of 53.7<i>μ</i>C cm^-2. Besides, compared to the undoped and UD HZO films, the OD samples exhibit enhanced dielectric performance, with lower leakage currents and higher breakdown voltages, suggesting that the optimized distribution suppresses oxygen vacancy generation and mitigates defect formation. Furthermore, the OD samples maintain a large 2<i>P</i>_rof 40.4<i>μ</i>C cm^-2after 10^8,which can be rejuvenated back to 50.7<i>μ</i>C cm^-2by higher voltage cycling. The enhanced dielectric performances and reversible phase transitions during cycling underline the potential of Al-doped HZO films with optimized distribution as reliable, long-endurance FE materials, advancing the development of HfO₂-based FE devices for future memory applications.</p>","PeriodicalId":19035,"journal":{"name":"Nanotechnology","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143059844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Engineered ultra-wide bandgap Sm₂O₃/MWCNT nanocomposites for deep-ultra violet photodetectors.","authors":"Afsal Sharaf, Shantikumar Nair, Laxman Raju Thoutam","doi":"10.1088/1361-6528/adab7d","DOIUrl":"https://doi.org/10.1088/1361-6528/adab7d","url":null,"abstract":"<p><p>The current work focuses on the synthesis and control of cubic vs monoclinic phase structures of Sm₂O₃via., cost-effective solution-based sol-gel technique. The structural analysis of the as-synthesized Sm₂O₃powder reveals the phase-change from initial mixture of cubic and monoclinic phases (82:18) to almost cubic phase (96:4), with increase of polyethylene glycol 600 additive from 2% to 25% respectively. The dark-current of the films made from as-synthesized Sm₂O₃powder revealed no measurable current, indicates its high defect tolerance against growth conditions. The multi-walled carbon nanotubes (MWCNT) are added as conducting scaffold into Sm₂O₃insulating matrix, to facilitate carrier transport for light-generated carriers, upon UV exposure. The dark-current of the photodetectors increased from nano-ampere to milli-ampere range with increase in MWCNT weight concentration from 1% to 10% respectively. A nominal photo-to-dark current ratio (PDCR) of around 2 is observed for different MWCNT concentrations in Sm₂O₃on glass substrates, upon UV light exposure. The PDCR is further increased to a maximum of 5.6 with the increase in grain-structure of Sm₂O₃within the nanocomposite via., substrate-engineering. The observed PDCR of 5.6 is the first reported value (to the best of our knowledge) for Sm₂O₃-based nanocomposite material towards deep-UV photodetector applications. The experimental results suggest incorporation of conductive nanocomposites into ultra-wide bandgap oxide semiconductor materials seems to be a feasible and promising approach for the design of future cost-effective deep-UV photodetectors.</p>","PeriodicalId":19035,"journal":{"name":"Nanotechnology","volume":"36 13","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143255996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Accurate operando measurement of AlGaN/GaN HEMTs channel temperature and optimization of thermal design.","authors":"Ruihua An, Jinyan Zhao, Shijie Zhai, Jun Yang, Jie Li, Wenbo Hu, Liyan Dai, Qiang Wang, Guipeng Sun, Yang Fan, Shengli Wu, Gang Niu","doi":"10.1088/1361-6528/adafaf","DOIUrl":"10.1088/1361-6528/adafaf","url":null,"abstract":"<p><p>The accurate estimation of the temperature distribution of the GaN based power devices and optimization of the device structure is of great significance to possibly solve the self-heating problem, which hinders the further enhancement of the device performances. We present here the operando temperature measurement with high spatial resolution using Raman spectroscopy of AlGaN/GaN high electron mobility transistors (HEMTs) with different device structures and explore the optimization of the device thermal design accordingly. The lateral and depth temperature distributions of the single-finger HEMT were characterized. The channel temperature and self-heating effect of the device under different bias voltages were investigated. By incorporating the two-dimensional electrothermal simulation, the hotspot position can be clearly observed under the gate edge near the drain side. The channel temperature of the multi-finger HEMT was further measured and the experiment results were in agreement with the three-dimensional finite element analysis simulation results. The device structure of the multi-finger device, including the gate width, gate pitch, structure layout, substrate materials, and thickness, were then theoretically optimized to improve the heat dissipation. The peak channel temperature of the device can be reduced by 70 °C when the substrate is substituted from silicon carbide to a single crystalline diamond. These results are of great interest for the thermal management of GaN HEMT power devices and further device performance improvement.</p>","PeriodicalId":19035,"journal":{"name":"Nanotechnology","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143066854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optical properties of quasi-two-dimensional GaAs/AlGaAs nanosheets prepared by releasing epitaxial layer.","authors":"Bowen Zhang, Yu Hao, Chao Shi, Shuangshuang Pu, Xiaohua Wang, Dengkui Wang, Dan Fang, Hao Yan, Jinhua Li, Xuan Fang","doi":"10.1088/1361-6528/adad79","DOIUrl":"10.1088/1361-6528/adad79","url":null,"abstract":"<p><p>Quasi-two-dimensional nanosheets exhibit novel properties and promising applications in optoelectronic flexible devices. Research on non-layered III-V semiconductor nanosheets has been constrained by their covalent bonding connections. In this study, GaAs/AlGaAs heterojunction nanosheets were prepared by releasing an epitaxial layer, and their optical properties were investigated by adopting steady-state and transient absorption spectroscopy. The optical properties of the independent GaAs/AlGaAs heterojunction were investigated separately in order to exclude the effect of the substrate. This work provides a comprehensive understanding of the physics of III-V semiconductor quasi-two-dimensional nanosheets.</p>","PeriodicalId":19035,"journal":{"name":"Nanotechnology","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143029228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Computational simulation of graphene/h-BN nanopores for single-molecule herbicide sensing.","authors":"Wanderlã L Scopel, Fábio A L de Souza, Sávio B de Souza, Rodrigo G Amorim, Ralph H Scheicher","doi":"10.1088/1361-6528/adac67","DOIUrl":"10.1088/1361-6528/adac67","url":null,"abstract":"<p><p>The growing world population and climate change are key drivers for the increasing pursuit of more efficient and environmentally-safe food production. In this scenario, the large scale use of herbicides demands the development of new technologies to control and monitor the application of these compounds, due to their severe environmental and health-related problems. Motivated by these issues, in this work, a hybrid graphene/boron nitride nanopore is explored to detect/identify herbicide molecules (Glyphosate, aminomethylphosphonic acid, Diuron, and 2,4D). Solid-state nanopores based on 2D materials have been widely explored as novel generation sensors capable of single-molecule resolution. The present investigation combines density functional theory (DFT) and the non-equilibrium Green's function method to assess the interaction of each herbicide with the nanopore and how its interaction modulates the device's electronic transport properties. The device's sensitivity spreads from 9.0% up to 27.0% when probed at different gate voltages. Overall, the proposed device seems to be sensitive and selective to be considered as a promising single-molecule herbicide sensor.</p>","PeriodicalId":19035,"journal":{"name":"Nanotechnology","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143008788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A special two-working-electrode system: a summary of recent development in fabrication and application of interdigitated array electrodes.","authors":"Tingsen Zhang, Yingying Jian, Zhiyong Deng, Weiwei Wu, Fei Liu","doi":"10.1088/1361-6528/adae15","DOIUrl":"10.1088/1361-6528/adae15","url":null,"abstract":"<p><p>The utilization of two-working-electrode mode of interdigitated array (IDA) electrodes and other two-electrode systems has revolutionized electrochemical detection by enabling the simultaneous and independent detection of two species or reactions. In contrast to conventional two-potential electrodes, such as the rotating ring disk electrodes, IDAs demonstrate analogous yet vastly improved performance, characterized by remarkable collection efficiency, sensitivity, and signal amplification resulted from the 'feedback' effect. In recent decades, the research surrounding IDAs has garnered escalating interest due to their attractive attributes. This review centers its focus on the recent development on the fabrication of IDA electrodes as well as their applications leveraging the unique electrochemical and structural features. In fabrication, two critical breakthroughs are poised for realization: the achievement of reduced dimensions and the diversification of materials. Established fabrication methods for IDA electrodes encompass photolithography, inkjet printing, and direct laser writing, each affording distinct advantages in terms of size and precision. Photolithography enables the creation with finer structures and higher resolution compared to others. Inkjet printing or laser writing provides a simpler, more cost-effective, and straightforward patterning process, albeit with lower resolution. In terms of applications, IDAs have found utility in diverse fields. This review summarizes recent applications based on their fundamental working principles, encompassing redox cycling, resistance modulation, capacitance variations, and more. This specialized tool shows great promise for further development with enhanced properties. It is also important to note that, micron- or sub-micron-sized IDAs generally cannot be reused, as their small structures cannot be polished. Therefore, controlling the cost of IDA fabrication is crucial for promoting their broader application. Additionally, the distinctive electrochemical properties of 'feedback' effect is often underappreciated. The high sensitivity of IDA electrodes, arising from the 'feedback' signal amplification mechanism, holds significant potential for the detection of species with short lifetimes or low concentrations.</p>","PeriodicalId":19035,"journal":{"name":"Nanotechnology","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143033686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of Ga-ion irradiation on sub-micron-wavelength spin waves in yttrium-iron-garnet films.","authors":"Johannes Greil, Martina Kiechle, Adam Papp, Peter Neumann, Zoltán Kovács, Janos Volk, Frank Schulz, Sebastian Wintz, Markus Weigand, György Csaba, Markus Becherer","doi":"10.1088/1361-6528/adad7d","DOIUrl":"10.1088/1361-6528/adad7d","url":null,"abstract":"<p><p>We investigate the effect of focused-ion-beam (FIB) irradiation on spin waves with sub-micron wavelengths in yttrium-iron-garnet films. Time-resolved scanning transmission x-ray microscopy was used to image the spin waves in irradiated regions and deduce corresponding changes in the magnetic parameters of the film. We find that the changes of Ga⁺irradiation can be understood by assuming a few percent change in the effective magnetizationMeffof the film due to a trade-off between changes in anisotropy and effective film thickness. Our results demonstrate that FIB irradiation can be used to locally alter the dispersion relation and the effective refractive indexneffof the film, even for submicron wavelengths. To achieve the same change innefffor shorter wavelengths, a higher dose is required, but no significant deterioration of spin wave propagation length in the irradiated regions was observed, even at the highest applied doses.</p>","PeriodicalId":19035,"journal":{"name":"Nanotechnology","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143029231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Solvent-modulated preparation of lead-free Cs₃Bi₂I₉polycrystalline film for high-performance photodetectors.","authors":"Yaoyao Song, Huiyin Zhang, Mengfan Liu, Yubo Wan, Hao Sun, Yang Cao","doi":"10.1088/1361-6528/adae16","DOIUrl":"10.1088/1361-6528/adae16","url":null,"abstract":"<p><p>Lead-free cesium bismuth iodide (Cs₃Bi₂I₉) perovskite exhibits extraordinary optoelectronic properties and attractive potential in various optoelectronic devices, especially the application for photodetectors (PDs). However, most Cs₃Bi₂I₉PDs demonstrated poor detection performance due to the difficulty in obtaining high-quality polycrystalline films. Therefore, it makes sense to modulate the preparation of high-quality Cs₃Bi₂I₉polycrystalline films and expand its applications. Here, a solvent-modulated method combining anti-solvent and precursor engineering has been developed to regulate the crystallization dynamics of Cs₃Bi₂I₉. Anti-solvent treatment is to suppress the asynchronous separation out of CsI and BiI₃due to significant differences in solubility, promoting uniform nucleation and limiting flake-like growth. Precursor engineering is synchronously used to modulate the subsequent nucleation growth dynamics. Due to the synergistic modulation, smooth and compact Cs₃Bi₂I₉polycrystalline films with distinct grains and grain boundaries can be easily obtained. The as-prepared PD exhibits an excellent on/off ratio of 4.26 × 10⁵as well as the detectivity up to 6.49 × 10¹⁰Jones at zero bias. And, the Cs₃Bi₂I₉PD indicates excellent device stability, maintaining about 70% of the original performance after being stored for 400 h in the air without encapsulation.</p>","PeriodicalId":19035,"journal":{"name":"Nanotechnology","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143033689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}