- 标题
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Localized Nanoresonator Mode in Plasmonic Microcavities
摘要： Submicron-thick hexagonal boron nitride crystals embedded in noble metals form planar Fabry-Perot half-microcavities. Depositing Au nanoparticles on top of these microcavities forms previously unidentified angle- and polarization-sensitive nanoresonator modes that are tightly laterally confined by the nanoparticle. Comparing dark-field scattering with reflection spectroscopies shows plasmonic and Fabry-Perot-like enhancements magnify subtle interference contributions, which lead to unexpected redshifts in the dark-field spectra, explained by the presence of these new modes.
关键词： dark-field scattering,plasmonic microcavities,nanoresonator mode,Au nanoparticles,hexagonal boron nitride
更新于2025-09-19 17:13:59
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Hexagonal Boron Nitride Phononic Crystal Waveguides
摘要： Hexagonal boron nitride (h-BN), one of the hallmark van der Waals (vdW) layered crystals with an ensemble of attractive physical properties, is playing increasingly important roles in exploring two-dimensional (2D) electronics, photonics, mechanics, and emerging quantum engineering. Here we report on the demonstration of h-BN phononic crystal waveguides with designed pass and stop bands in the radio frequency (RF) range, and controllable wave propagation and transmission, by harnessing arrays of coupled h-BN nanomechanical resonators with engineerable coupling strength. Experimental measurements validate that these phononic crystal waveguides confine and support 15 to 24 megahertz (MHz) wave propagation over hundreds of micrometers. Analogous to solid-state crystal lattices, phononic bandgaps and dispersive behaviors have been observed and systematically investigated in the h-BN phononic waveguides. Guiding and manipulating acoustic waves on such additively integratable h-BN platform may facilitate multiphysical coupling and information transduction, and open up new opportunities for coherent on-chip signal processing and communication via emerging h-BN photonic and phononic devices.
关键词： integrated phononics,phononic crystal waveguide,nanoelectromechanical systems (NEMS),acoustic wave,Hexagonal boron nitride (h-BN),radio frequency
更新于2025-09-19 17:13:59
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Plasmonically enabled two-dimensional material-based optoelectronic devices
摘要： Two-dimensional (2D) materials, such as graphene, transition metal dichalcogenides, black phosphorus and hexagonal boron nitride, have been intensively investigated as building blocks for optoelectronic devices in the past few years. Very recently, significant efforts have been devoted to the improvement of the optoelectronic performances of 2D materials, which are restricted by their intrinsically low light absorption due to the ultrathin thickness. Making use of the plasmonic effects of metal nanostructures as well as intrinsic plasmon excitation in graphene has been shown to be one of the promising strategies. In this minireview, recent progresses in 2D material-based optoelectronics enabled by the plasmonic effects are highlighted. A perspective on more possibilities in plasmon-assisted 2D material-based optoelectronic applications will also be provided.
关键词： Transition metal dichalcogenides,Plasmonic effects,Two-dimensional materials,Black phosphorus,Hexagonal boron nitride,Graphene,Optoelectronic devices
更新于2025-09-19 17:13:59
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Boron nitride/sulfonated polythiophene composite electro-catalyst as the TCO and Pt-free counter electrode for dye-sensitized solar cells: 21% at dim light
摘要： Boron nitride (BN) is newly introduced as a non-metal electro-catalyst for the counter electrode of a dye-sensitized solar cell (DSSC). By applying a conductive binder of sulfonated poly(thiophene-3-[2-(2-methoxyethoxy)ethoxy]-2,5-diyl) (s-PT), the BN/s-PT composite film was successfully wrapped around each carbon fiber (CF) in the flexible carbon cloth (CC) substrate via a low-cost drop-coating method. Each CF in CC provided a one-dimensional electron transfer core, and the wrapped BN/s-PT composite film functioned as the mesoporous electro-catalytic shell. Compared to pristine BN and pristine s-PT electrodes, the electrochemical and impedance performances of the BN/s-PT composite film were incredibly enhanced due to the synergetic effect of BN nanoparticle and s-PT binder; the former offered large active surface area and high intrinsic heterogeneous rate constant, the latter formed fast electron transfer matrices. With a proper BN weight percentage among BN/s-PT solutions, the best DSSC coupling with a BN/s-PT composite counter electrode exhibited a good cell efficiency (η) of 9.21% at 1 sun, showing a great potential to substitute the expensive platinum (8.11%). At the dim light environment (i.e., T5 fluorescent illumination), the DSSC reached attractive η’s of 21.02% (6000 lux), 19.52% (3000 lux), and 17.48% (1000 lux).
关键词： boron nitride,DSSC,dim light,sulfonated polythiophene,counter electrode
更新于2025-09-19 17:13:59
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Decoding the structure of interfaces and impurities in 2D materials by photoelectron holography
摘要： The properties of atomically thin materials essentially depend on their structures, including impurities, defects and interfaces with underlying substrates. Thus, the detailed structural information is relevant for creation of 2D materials with desired properties. Here, we explore the capabilities of photoelectron diffraction and holography for structural analysis of atomically thin layers using as examples such systems as h-BN, graphene, and modified graphene with boron impurities. We show that for planar 2D crystals with commensurate interface to the substrate, it is possible to visualize the interface and impurities with high spatial resolution, and to distinguish possible non-equivalent structural units. Our approach applied to B-doped graphene on Ni(1 1 1) and Co(0 0 0 1) surfaces has allowed to reveal asymmetry of boron concentrations in the two carbon sublattices and established its dependence on the applied synthesis procedure and chosen substrate. The obtained results suggest that such approach can be widely applied for studies of various 2D systems, where the structures of interfaces and defects are of remarkable importance.
关键词： doping,structure,photoelectron diffraction,graphene,hexagonal boron nitride,photoelectron holography
更新于2025-09-19 17:13:59
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Optimization of Boron Spin on Dopant (BSoD) Diffusion for Emitter Formation in n-type c-Si Solar Cells
摘要： Boron spin on dopant (BSoD) is an alternative boron source to BBr3 liquid dopant for p+ emitter formation in n-type solar cells. In this work, we have used different process control steps to lower the BSoD diffusion issues to have a uniform sheet resistance of p+ emitters. After eliminating the boron (B) precipitates formed during the process of diffusion by control process steps, the emitters have been optimized for sheet resistance values ≤60?/□ with variation less than ±5?/□. The corresponding junction depth is less than 800nm as measured by SIMS analysis. All the experiments are carried out with Czochralski n-type c-Si wafers which showed an improvement of effective minority carrier lifetimes by more than 2 times in controlled process steps. The measured Sun’s Voc and implied Voc are in the range 575- 600mV without any passivation. The PC1D simulation shows the efficiency of the solar cell without any passivation is 14.8%. This indicates the BSoD as a promising source for the p+ emitter formation in n- type c-Si solar cells.
关键词： boron rich layer,Sheet resistance,boron spin on dopant,PC1D simulation
更新于2025-09-16 10:30:52
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Multivariate determination of 10B isotopic ratio by laser-induced breakdown spectroscopy using multiple BO molecular emissions
摘要： Measurements of boron isotopic ratios have been investigated using LIBS, and combined LIBS and Molecular laser-induced fluorescence (MLIF). Mixtures of various ratios of research grade H3 11BO3 and H3 10BO3 in pellet form were interrogated with a Q-switched Nd:YAG laser operating at 532 nm. The resulting plasma was examined for their BO molecular bands in the 254–262 nm and 266–276 nm wavelength ranges. A minimum of three band heads of the β system B2Σ → X2Σ transitions were identified. The rovibronic isotopic shifts of the corresponding bands were measured and were conclusively compared to the literature. MLIF was applied to LIBS emission lines covering 253–271 nm to enhance some band heads, selectively. Both LIBS and LIBS-MLIF emissions were subject to multivariate statistical analysis to predict 10B isotopic ratios. Two PLS regression calibration models were examined to better examine the effects, sensitivity, accuracy of the laser-produced plasma excitation modalities based models through the figure of merit. For the full calibration set (21 samples), the root mean square error of cross-validation (RMSECV), the pseudo univariate LOD (LODpu) and the LOD interval ([LODmin, LODmax]) for 10B isotopes were improved from 1.61%, 4.81%, [2.64%, 3.49%] 10B isotopic ratio, respectively for LIBS to 0.98%, 2.40%, [2.19%, 2.81%] 10B isotopic ratio, respectively for LIBS-MLIF. However, using a random subset of the samples (14) as a calibration set and the rest as a test set, the root mean square error of prediction of 10B isotopic ratio in the test set improved from 2.95% to 1.16% 10B isotopic ratio, respectively for LIBS and LIBS-MLIF; and the LOD interval improved from [2.45%, 2.69%] to [1.88%, 2.12%] 10B isotopic ratio when calculated with cross-validated residual variance. Moreover, the prediction error of a test set improved from 2.95% for LIBS to 1.16% for LIBS-MLIF.
关键词： Molecular laser-induced fluorescence,LIBS-MLIF,Limit of detection interval,Laser-induced breakdown spectroscopy,Boron isotopes,Molecular band
更新于2025-09-16 10:30:52
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Radiology, Lasers, Nanoparticles and Prosthetics || 11. Neutron radiotherapy
摘要： Neutrons like protons are hadrons, however neutrons are uncharged. They are more difficult to produce, and because they are neutral, accelerators and magnets cannot be used for tuning their energy or steering the beam. Neutron irradiation requires a neutron source and a radiological shielding environment that are very different to those for charged particles. Among the various external radiation treatments of cancer, neutron radiation therapy is presently not often prescribed.
关键词： fast neutrons,RBE,Boron Neutron Capture Therapy,BNCT,linear energy transfer,Neutron radiotherapy,LET,relative biological effectiveness
更新于2025-09-16 10:30:52
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Defect Formation in Ion-Implanted Si - Approach to Controlled Semiconductor Optical Properties
摘要： For specific modification of the fundamental optical and photoelectrical properties of silicon transparent for wavelengths beyond 1.1μm, boron ions have been implanted into n-type wafers at doses of 1 х 1013 cm-2–1 х 1015 cm-2 followed by annealing at 900 °C and 1000 °C (20 min). The IR reflection spectra, Raman spectroscopy and scanning electron microscopy data have been compared with the photosensitivity spectra (1.4–2.2 μm) and with the integrated photoresponse in the IR (1.0–4.1 μm) and UV (0.25–0.4 μm) regions. These studies allow for materials engineering to obtain new data on the influence of defect formation on the optical properties of the material and to evaluate the technological conditions for practical application of the modified material.
关键词： Boron ion implanted silicon,IR and UV photosensitivity,IR reflection spectra,p-n structures,extended defects,Raman-spectroscopy
更新于2025-09-16 10:30:52
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Highly focused femtosecond laser directed selective boron doping in single SiC nanowire device for n-p conversion
摘要： In this work, site-selective Boron (B) doping in SiC nanowires has been demonstrated by utilizing focused femtosecond (fs) laser irradiation. Raman spectra and electrical performance indicate that the localized element doping in pristine n-type SiC nanowires can convert the segment into p-type. The formation of crystalline defects and vacancies in nanowires under fs laser irradiation, along with the simultaneous dissociation of the dopant molecules, can accelerate the doping process. Single SiC nanowire p-n junction and ?eld-effect transistors with a p-type segment have been fabricated based on the pristine n-type nanowire, showing a modi?ed electrical response as a logic gate to programmed voltage signals. This laser controlled selective doping may provide an alternative for precise element doping in semiconductors at the nanoscale, which can be promising for nanoelectronic unit fabrication.
关键词： SiC nanowire,femtosecond laser,n-p conversion,nanoelectronics,boron doping
更新于2025-09-16 10:30:52