- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Photoactive Functional Soft Materials (Preparation, Properties, and Applications) || A Photoresponsive Multi-Bilayered Film for a Tunable Photonic Crystal
摘要： Over the last half‐century, advances in science based on the evolution of semiconductor physics and transistor electronics have greatly influenced the development of our lives. The key to this was the ability to design crystalline materials that tailor the conduction properties of electrons to suit diverse applications. More recently, the optical communication revolution has shifted the frontier in high‐speed, multiplex, and wide‐bandwidth information processing from electrons to photons, a shift that demands a new kind of synthetic soft material to mold the gigabits. To address this need, recent research has suggested a way to tailor the propagation of light much like that of electrons, via the creation of periodic optical media dubbed photonic crystals (PCs).
关键词： azobenzene,photonic crystals,multi‐bilayered film,photoresponsive,tunable
更新于2025-09-23 15:21:01
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Self-Powered Humidity Sensor Using Chitosan-Based Plasmonic Metal-Hydrogel-Metal Filters
摘要： A tunable Fabry–Pérot resonator is realized using metal–insulator–metal structure, in which the insulator is chitosan hydrogel. The chitosan swells in response to changes in relative humidity; this change affects transmissive structural color of the multilayer structure. This tunable resonator is utilized for a humidity sensor combined with a photovoltaic cell. The change in current through the photovoltaic cell provides rapid precise measurement of relative humidity, and the change in color of the multilayer provides an approximate, remotely-readable estimate. The response requires no power, so the device has numerous sensing applications.
关键词： Fabry–Pérot etalon,structural colors,tunable color filter,tunable structural colors,interferometric colors,metal–insulator–metal
更新于2025-09-23 15:19:57
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Complementary doping of van der Waals materials through controlled intercalation for monolithically integrated electronics
摘要： Doping control has been a key challenge for electronic applications of van der Waals materials. Here, we demonstrate complementary doping of black phosphorus using controlled ionic intercalation to achieve monolithic building elements. We characterize the anisotropic electrical transport as a function of ion concentrations and report a widely tunable resistivity up to three orders of magnitude with characteristic concentration dependence corresponding to phase transitions during intercalation. As a further step, we develop both p-type and n-type field effect transistors as well as electrical diodes with high device stability and performance. In addition, enhanced charge mobility from 380 to 820 cm2/(V·s) with the intercalation process is observed and explained as the suppressed neutral impurity scattering based on our ab initio calculations. Our study provides a unique approach to atomically control the electrical properties of van der Waals materials, and may open up new opportunities in developing advanced electronics and physics platforms.
关键词： nanoelectronics,two-dimensional (2D) materials and heterostructures,tunable properties,diode,black phosphorus,FET
更新于2025-09-23 15:19:57
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Ultrahigh resolution spectroscopy for dimethyl sulfide at the ??1- and ??8-bands by a distributed feedback interband cascade laser
摘要： The ultrahigh-resolution, air-broadened mid-infrared absorption spectrum of dimethyl sulfide (DMS) was recorded in the spectral region of 2994.17–2999.03 cm?1, where the strong ν1-/ν8-bands are located. Benefitting from the tunable laser absorption spectrometry with a distributed feedback interband cascade laser, the spectral resolution achieved 5.69 × 10?6 cm?1. The recorded spectra of DMS are very close to that in the Pacific Northwest National Laboratory (PNNL) database, however it has a much lower absorbance uncertainty of 0.38%. And the maximum relative difference of the full width at half maximum and the integrated area of spectral peaks between the recorded spectra and the PNNL data are as large as 16.7% and 27.9%, respectively, which could mainly come from the difference of the spectral resolution. The more accurate reference spectrum is hopeful to be applied to absolute measurement and remote sensing for gaseous DMS.
关键词： Tunable laser absorption spectroscopy (TLAS),Dimethyl sulfide (DMS),Ultrahigh-resolution spectrum,Interband cascade laser (ICL),Mid-infrared
更新于2025-09-23 15:19:57
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Development of a composite polymer-dye medium for tunable laser emission
摘要： We demonstrate optically pumped laser medium with emission in the visible spectral range from binary solutions of Rhodamine 6G and Rhodamine B in epoxy resin as matrix without appending additional scattering centers. A frequency doubled Q-switched Nd: YAG laser was used for pumping. The generation’s behavior is similar to random laser (RL) with no external optical resonator. The in?uence of the nanostructured morphology of the medium on the laser properties was investigated by means of SEM, AFM, TEM, SAED, Spectro?uorimetry and Spectrometry. The laser emission is characterized by high intensity – energy per pulse – 300 μJ, threshold pump energy 1.7 mJ, relatively low beam divergence of 70 mrad (for RL) and spectrally narrowed major peak at 597 nm. The new gain medium was also investigated in a conventional tunable resonator. Generation with continuous tuning in the spectral range 590–610 nm was obtained. This new e?ective nanostructured medium, which shows with high optical and energy parameters, can be used in speckle-free laser imaging, time-resolved microscopy, high speed optical converters and others photonics applications.
关键词： Dye laser,Tunable laser,Broadband laser,Random laser,Epoxy resin
更新于2025-09-23 15:19:57
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Flattop output extra-wide tuning range tunable laser design technique
摘要： The laser oscillator design principle, which provides extended tunability together with a flattop output in the wide spectral range, is proposed and demonstrated on the examples of the dye laser. It is realized by using an high-reflecting (HR) moving intracavity mirror (scraper) with the sharp edge partially overlapping the laser radiation in the high-Q cavity and extracting it out. The technique provides the output laser beam with M2 < 1.2 and can be applied to any type of lasers operating from the far-IR to the VUV spectral ranges. Besides, wide-band HR cavity mirrors are only used, and there are no special demands to the material of the mirror substrate.
关键词： laser efficiency,output coupler optimization,tunable lasers
更新于2025-09-23 15:19:57
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Experimental observation of the vibration-rotation radiation curves of <sup>12</sup> C <sup>16</sup> O <sub/>2</sub> and <sup>13</sup> C <sup>16</sup> O <sub/>2</sub> absorption constants ranging from 4860 to 4880 sm <sup>a??1</sup> by the tunable diode laser absorption spectroscopy method
摘要： We report the experimental observation of the absorption constant values of 12C16O2 and 13C16O2 using the tunable diode laser absorption spectroscopy method ranging from 4860 to 4880 sm?1 within the pressure limits of 8–240 mbar for the absorption curves (lines) R(18), R(20), R(22), R(24), R(26), R(28), R(30), R(32), R(34) and R(36) of the 20013–00001 molecule 12C16O2 vibration band, and within the pressure limits of 0.06–1.7 mbar for the absorption curves P(10), P(12), P(14), P(16), P(18), P(20) and P(22) of the 20012–00001 molecule 13C16O2 vibration band. In the work, as a mixture under analysis, a mixture of the isotopes 13C16O2 and 12C16O2 at the ratio of 1:140 was used. The results have been compared with the data of the HITRAN spectroscopic database.
关键词： tunable diode laser absorption spectroscopy,carbon dioxide,absorption coefficients
更新于2025-09-23 15:19:57
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Gas distribution mapping for indoor environments based on laser absorption spectroscopy: Development of an improved tomographic algorithm
摘要： Gas distribution mapping (GDM) is an important technology for the study of indoor environment, which can be used to evaluate the efficiency of environmental control system and identify pollutant sources. Most recent studies have implemented GDM through contact sensors or a sensor network, which is difficult to calibrate all the sensors and cover the whole space. In this study, we introduced the non-contact tunable diode laser absorption spectroscopy (TDLAS) technology for GDM in the indoor environment. An improved tomographic algorithm, namely Least Square with Tikhonov Regularization (LSTR), was proposed and compared with two available tomographic algorithms using four validated computational fluid dynamics (CFD) simulations. We also analyzed the effects of the laser emitter placements and optical path densities on the concentration field reconstruction quantitatively. The results showed that the LSTR method could reduce the average relative root mean square error (RRMSE) of tomography by 52%, and the laser emitter at the long edge middle (LEM) can achieve better tomographic performance. The degree of the concentration dispersion from the source would mainly impact the tomographic results: when the sector dispersion (SD) value of concentration distribution was about 2.3 times larger, the average RRMSE value would be decreased by about 40%. The intersection matrix with a higher path density achieved a more accurately reconstructed map due to its lower condition number. In addition, the optical path density was suggested to twice the number of grid cells considering the trade-off between scanning time and accuracy.
关键词： Non-contact sensing,Tunable diode laser absorption spectroscopy (TDLAS),Concentration measurement,Indoor air,Air pollution
更新于2025-09-23 15:19:57
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Development of a Flexible Tunable and Compact Microstrip Antenna via Laser Assisted Patterning of Copper Film
摘要： Design and rapid prototyping of a tunable and compact industrial, scientific and medical (ISM) band microstrip antenna for applications is presented in this paper. Laser machining is introduced as a fast and accurate method for the antenna fabrication. The antenna, with an overall dimension of 65 × 46 × 0.127 mm, was fabricated by sandwiching a flexible Kapton polyimide substrate, with a dielectric constant of 3.5, between two flexible copper tapes, as the radiating patch and ground plane, respectively. The radiating patch was patterned in a meander configuration, with three slots, demonstrating the capability to reduce the resonant frequency of the microstrip antenna from 2.4 GHz to 900 MHz, without increasing the overall size of the antenna (87% compact). The effect of mechanical stress on the antenna performance was investigated by performing bend and stretch tests. The antenna was subjected to compressive bend with a minimum radius of curvature of 86 mm and 150 mm along the x- axis and y- axis which resulted in a maximum increase of resonant frequency by 3.1% and 1.3%, respectively. Similarly, the antenna was subjected to tensile bend with a minimum radius of curvature of 79 mm and 162 mm along the x- axis and y- axis which resulted in a maximum decrease of the resonant frequency by 4.2% and 0.3%, respectively. An overall 0.9% decrease in the resonant frequency was measured for an applied strain of 0.09% during stretching the antenna along the y- axis.
关键词： mechanical stress,flexible Kapton substrate,Compact tunable antenna,microstrip patch antenna,laser machining
更新于2025-09-23 15:19:57
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Polarization-enabled tunable focusing by visible-light metalenses with geometric and propagation phase
摘要： Flat metalenses with tunable focal length have wide applications in modern optical systems with high integration requirement. Here, by combining propagation phase and geometric phase, we numerically realize a metalens with a tunable focal length by controlling the polarization state of incident light. The tuning range can be as large as 15λ at the designer wavelength. Furthermore, the tunable performance can operate at the entire visible band with an ef?ciency over 35%. We believe that the proposed polarization-enabled tunable focusing metalens will ?nd signi?cant applications in imaging and sensing applications.
关键词： tunable focusing,metalens,polarization state,geometric phase
更新于2025-09-23 15:19:57