- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
High-Resolution Shortwave Infrared Imaging of Vascular Disorders Using Gold Nanoclusters
摘要： We synthesized a generation of water-soluble, atomically precise gold nanoclusters (Au NCs) with anisotropic surface containing short dithiol pegylated chain (AuMHA/TDT). These AuMHA/TDT exhibit a high brightness (QY～6%) in the shortwave infrared (SWIR) spectrum with a detection above 1250 nm. Furthermore, they show an extended half-life in blood (t1/2? = 19.54 ±0.05 h) and a very weak accumulation in organs. We also developed a non-invasive, whole-body vascular imaging system in the SWIR window with high-resolution, benefiting from a series of Monte Carlo image processing of the images. The imaging process enabled to improve contrast by one order of magnitude and enhance by 59% the spatial resolution. After systemic administration of these nanoprobes in mice, we can quantify vessel complexity in depth (> 4 mm) allowing to detect very subtle vascular disorders non-invasively in bone morphogenetic 9 (Bmp9) deficient mice. The combination of these anisotropic surface charged gold nanoclusters plus an improved SWIR imaging device allows then a precise mapping at high resolution and in depth of the organization of the vascular network in live animals.
关键词： shortwave infrared fluorescence,bone morphogenetic 9 (Bmp9),gold nanoclusters,vascular disorder,monte carlo restoration imaging processing
更新于2025-09-23 15:21:01
-
Mercury Chalcogenide Nanoplateleta??Quantum Dot Heterostructures as a New Class of Continuously Tunable Bright Shortwave Infrared Emitters
摘要： Despite broad applications in imaging, energy conversion and telecommunications, there are few nanoscale moieties that emit light efficiently in the shortwave infrared (SWIR, 1000-2000 nm or 1.24-0.62 eV). We report quantum confined mercury chalcogenide (HgX, X=Se, Te) nanoplatelets (NPLs) can be induced to emit bright (QY >30%) and tunable (900-1500+ nm) infrared emission from attached quantum dot (QD) “defect” states. We demonstrate near unity energy transfer from NPL to these QDs, which completely quench NPL emission and emit with high QY through the SWIR. This QD defect emission is kinetically tunable, enabling controlled mid-gap emission from NPLs. Spectrally resolved photoluminescence demonstrates energy dependent lifetimes, with radiative rates 10-20 times faster than their PbX analogs in the same spectral window. Coupled with their high quantum yield, mid-gap emission HgX dots on HgX NPLs provides a potential platform for novel optoelectronics in the SWIR.
关键词： nanoplatelets,shortwave infrared,mercury chalcogenide,optoelectronics,quantum dots
更新于2025-09-23 15:19:57
-
Orthogonal Shortwave Infrared Emission Based on Rare Earth Nanoparticles for Interference-free Logical Code and Bio-imaging
摘要： Shortwave infrared (SWIR) photoluminescence has received intense interest in many fields in the recent years thanks to the advantages of its wide wavelength, high tissue imaging ability and it is invisible to the naked eye. However, achieving orthogonal SWIR emission still remains challenge. In the present study, synthesized NaErF4@NaLuF4 (Er@Lu) and NaYF4:Nd@NaLuF4 (Y:Nd@Lu) nanoparticles emitted atom-liked SWIR emission, respectively, and the separated distance between the SWIR emission was beyond 50 nm, which permitted orthogonal SWIR signal acquirement with optical filters. Furthermore, we designed an invisible logical code by manipulating the orthogonal SWIR emission of the lanthanide fluoride nanoparticles, which was further operated by basic logical operations and applied in information encryption and anti-counterfeit. In addition, the emission between these two hydrophilic nanoparticles could be also separated in vivo without signals interference and the orthogonal SWIR imaging mode was achieved, which was demonstrated in bio-imaging experiment in vivo. This demonstration extended the orthogonal SWIR emission capacity by controlling the orthogonal emission, opening new opportunities in the data security, diseases diagnosis and non-interference label in vivo.
关键词： bio-imaging,anti-counterfeit,Orthogonal shortwave infrared,SWIR logical codes,lanthanide fluoride nanoparticles
更新于2025-09-19 17:15:36
-
Interlayer Transition in a vdW Heterostructure toward Ultrahigh Detectivity Shortwave Infrared Photodetectors
摘要： Van der Waals (vdW) heterostructures of 2D atomically thin layered materials (2DLMs) provide a unique platform for constructing optoelectronic devices by staking 2D atomic sheets with unprecedented functionality and performance. A particular advantage of these vdW heterostructures is the energy band engineering of 2DLMs to achieve interlayer excitons through type-II band alignment, enabling spectral range exceeding the cutoff wavelengths of the individual atomic sheets in the 2DLM. Herein, the high performance of GaTe/InSe vdW heterostructures device is reported. Unexpectedly, this GaTe/InSe vdWs p–n junction exhibits extraordinary detectivity in a new shortwave infrared (SWIR) spectrum, which is forbidden by the respective bandgap limits for the constituent GaTe (bandgap of ≈1.70 eV in both the bulk and monolayer) and InSe (bandgap of ≈1.20–1.80 eV depending on thickness reduction from bulk to monolayer). Specifically, the uncooled SWIR detectivity is up to ≈1014 Jones at 1064 nm and ≈1012 Jones at 1550 nm, respectively. This result indicates that the 2DLM vdW heterostructures with type-II band alignment produce an interlayer exciton transition, and this advantage can offer a viable strategy for devising high-performance optoelectronics in SWIR or even longer wavelengths beyond the individual limitations of the bandgaps and heteroepitaxy of the constituent atomic layers.
关键词： interlayer transitions,2D materials,vdW heterostructures,broadband photodetectors,shortwave infrared
更新于2025-09-19 17:13:59
-
Ancient Greek text concealed on the back of unrolled papyrus revealed through shortwave-infrared hyperspectral imaging
摘要： Only a few Herculaneum rolls exhibit writing on their reverse side. Since unrolled papyri are permanently glued to paperboard, so far, this fact was known to us only from 18th-century drawings. The application of shortwave-infrared (SWIR; 1000-2500 nm) hyperspectral imaging (HSI) to one of them (PHerc. 1691/1021) has revealed portions of Greek text hidden on the back more than 220 years after their first discovery, making it possible to recover this primary source for the ongoing new edition of this precious book. SWIR HSI has produced better contrast and legibility even on the extensive text preserved on the front compared to former imaging of Herculaneum papyri at 950 nm (improperly called multispectral imaging), with a substantial impact on the text reconstruction. These promising results confirm the importance of advanced techniques applied to ancient carbonized papyri and open the way to a better investigation of hundreds of other such papyri.
关键词： ancient Greek text,shortwave-infrared hyperspectral imaging,Philodemus’ History of the Academy,text reconstruction,Herculaneum papyri
更新于2025-09-16 10:30:52
-
Photodetector of Shortwave Infrared Range of Format 640 × 512 Elements with Increased Dynamic Range
摘要： The paper substantiates the necessity of expanding the dynamic range in a shortwave infrared (SWIR) photodetector (PD). The traditionally used methods have low efficiency, especially in large-format matrices with a step of not more than 15 μm. The greatest efficiency of expanding the dynamic range (up to 100 dB) is provided by accumulative cells with individually variable transfer characteristic depending on the brightness of the fragments of the observed scene. The paper proposes a simple, in topological implementation, and effective way of expanding the dynamic range based on the auto-tuning of accumulation time individually in each cell of the integrated reading circuit. At the same time, the high steepness and linearity of the transformation in the storage cells with moderate illumination (up to 50–70% of the maximum signal) remains, but the sensitivity in the cells close to saturation decreases. As a result, a linear-log transfer characteristic is formed, providing an extended dynamic range. The paper provides examples of images with an extended dynamic range obtained using the first domestic SWIR camera of format 640 × 512 elements.
关键词： photodiodes,InGaAs,LSI readout,shortwave infrared range,expansion of the dynamic range,photodetectors
更新于2025-09-12 10:27:22
-
Solution-Processed Phototransistors Combining Organic Absorber and Charge Transporting Oxide for Visible to Infrared Light Detection
摘要： This report demonstrates high-performance infrared phototransistors that uses a broadband absorbing organic bulk heterojunction (BHJ) layer responsive from the visible to the shortwave infrared, from 500 nm to 1400 nm. The device structure is based on a bilayer transistor channel that decouples charge photogeneration and transport, enabling independent optimization of each process. The organic BHJ layer is improved by incorporating camphor, a highly polarizable additive that increases carrier lifetime. An indium zinc oxide transport layer with high electron mobility is employed for rapid charge transport. As a result, the phototransistors achieve a dynamic range of 127 dB and reach a specific detectivity of 5×1012 Jones under low power illumination of 20 nW/cm2, outperforming commercial germanium photodiodes in the spectral range below 1300 nm. The photodetector metrics are measured with respect to the applied voltage, incident light power, and temporal bandwidth, demonstrating operation at the video-frame rate of 50 Hz. In particular, the frequency and light dependence of the phototransistor characteristics are analyzed to understand the change in photoconductive gain under different working conditions.
关键词： shortwave infrared,phototransistor,indium zinc oxide,bulk heterojunction,carrier lifetime,semiconducting polymer,camphor
更新于2025-09-11 14:15:04
-
[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Building a Hyperspectral Library and its Incorporation into Sparse Unmixing for Mineral Identification
摘要： The objective of the SOLSA project (EU-H2020) is to develop an analytical expert system for on-line-on-mine-real-time mineralogical and geochemical analyses on sonic drill cores. As one aspect of the system, this paper presents the building of the hyperspectral library and its incorporation into sparse unmixing techniques for mineral identification. Twenty seven spectra representing 14 minerals have been collected for the library. Three sparse unmixing techniques have been investigated and evaluated using simulated data generated from our hyperspectral library, and real hyperspectral data acquired from a serpentinized harzburgite sample. Among the three techniques, the collaborative sparse unmixing by variable splitting and augmented Lagrangian (CLSUnSAL) method provided the best accurate results on the simulated data. In addition, the results of the CLSUnSAL method show high correlation with that of the QEMSCAN? analysis on the harzburgite hyperspectral data.
关键词： Hyperspectral library,sparse unmixing,shortwave infrared (SWIR)
更新于2025-09-04 15:30:14