Broadband SERS detection with disordered plasmonic hybrid aggregates

Plasmonic nanostructures possessing broadband intense field enhancement over a large area are highly desirable for nanophotonic and plasmonic device applications. In this study, 3D Ag hybrid nanoaggregates (3D-Ag-HNAs) are achieved via a highly efficient oblique angle gas-phase cluster beam deposition method. Not only can such structures produce a high density of plasmonic hot-spots to improve Raman sensitivity, but more importantly they generate kissing point-geometric singularities with a broadband optical response. We succeed in obtaining an experimental SERS enhancement factor beyond 4 × 107 in the visible range, providing an optimal sensing platform for different analytes. Combined with good uniformity, reproducibility and ease of fabrication, our 3D-Ag-HNA offers a candidate for new generations of SERS systems

Broadband single molecule SERS detection designed by warped optical spaces

Engineering hotspots is of crucial importance in many applications including energy harvesting, nano-lasers, subwavelength imaging, and biomedical sensing. Surface-enhanced Raman scattering spectroscopy is a key technique to identify analytes that would otherwise be difficult to diagnose. In standard systems, hotspots are realised with nanostructures made by acute tips or narrow gaps. Owing to the low probability for molecules to reach such tiny active regions, high sensitivity is always accompanied by a large preparation time for analyte accumulation which hinders the time response. Inspired by transformation optics, we introduce an approach based on warped spaces to manipulate hotspots, resulting in broadband enhancements in both the magnitude and volume. Experiments for single molecule detection with a fast soaking time are realised in conjunction with broadband response and uniformity. Such engineering could provide a new design platform for a rich manifold of devices, which can benefit from broadband and huge field enhancements

WashU Epigenome Browser update 2022

WashU Epigenome Browser (https://epigenomegateway.wustl.edu/browser/) is a web-based genomic data exploration tool that provides visualization, integration, and analysis of epigenomic datasets. The newly renovated user interface and functions have enabled researchers to engage with the browser and genomic data more efficiently and effectively since 2018. Here, we introduce a new integrated panel design in the browser that allows users to interact with 1D (genomic features), 2D (such as Hi-C), 3D (genome structure), and 4D (time series) data in a single web page. The browser can display three-dimensional chromatin structures with the 3D viewer module. The 4D tracks, called \u27Dynamic\u27 tracks, animatedly display time-series data, allowing for a more striking visual impact to identify the gene or genomic region candidates as a function of time. Genomic data, such as annotation features, numerical values, and chromatin interaction data can all be viewed in the dynamic track mode. Imaging data from microscopy experiments can also be displayed in the browser. In addition to software development, we continue to service and expand the data hubs we host for large consortia including 4DN, Roadmap Epigenomics, TaRGET and ENCODE, among others. Our growing user/developer community developed additional track types as plugins, such as qBed and dynseq tracks, which extend the utility of the browser. The browser serves as a foundation for additional genomics platforms including the WashU Virus Genome Browser (for COVID-19 research) and the Comparative Genome Browser. The WashU Epigenome Browser can also be accessed freely through Amazon Web Services at https://epigenomegateway.org/

Management of Abnormal Visual Developments

When human beings recognize the external world, more than 80% of the information come from visual function and visual system. Normal visual development and normal binocularity are the fundamental of good visual acuity and visual functions. Any abnormal visual experience would cause abnormality, such as refractive error, strabismus, amblyopia and other diseases. The patients with abnormal visual developments were reported to have abnormal, lonely, and other psycho problems. In this chapter, we will describe the normal developmental of visual function, summarize the abnormal developments and the correction or treatment

Microwave Synthesis and High‐Mobility Charge Transport of Carbon‐Nanotube‐in‐Perovskite Single Crystals

Organolead trihalide perovskites have emerged as a new class of competitive solution-processed semiconductors due to their unique optoelectronic properties. However, poor ambient stability and charge transport are the Achilles’ heel of hybrid perovskites, thus limiting their applications. In this work, microwave-assisted synthesis is applied for the first time to rapidly grow perovskite single crystals embedded with single-wall carbon nanotubes. These nanotube-in-perovskite single crystals are endowed with a carrier mobility one order of magnitude higher than the pure counterpart and the related photodetectors show an ultrafast photo-response speed (5 and 80 ns for rise and decay time, respectively). The fast and uniform heating of microwave irradiation facilitates the synthesis of ambient-stable crystals with nanoscale additives, paving the way to creating a wide range of mixed-dimensional perovskite-based nanocomposites with optimal properties and device performance

Ultrahigh Carrier Mobility Achieved in Photoresponsive Hybrid Perovskite Films via Coupling with Single-Walled Carbon Nanotubes

Organolead trihalide perovskites have drawn substantial interest for photovoltaic and optoelectronic applications due to their remarkable physical properties and low processing cost. However, perovskite thin films suffer from low carrier mobility as a result of their structural imperfections such as grain boundaries and pinholes, limiting their device performance and application potential. Here we demonstrate a simple and straightforward synthetic strategy based on coupling perovskite films with embedded single-walled carbon nanotubes. We are able to significantly enhance the hole and electron mobilities of the perovskite film to record-high values of 595.3 and 108.7 cm2 V−1 s−1, respectively. Such a synergistic effect can be harnessed to construct ambipolar phototransistors with an ultrahigh detectivity of 3.7 × 1014 Jones and a responsivity of 1 × 104 A W−1, on a par with the best devices available to date. The perovskite/carbon nanotube hybrids should provide a platform that is highly desirable for fields as diverse as optoelectronics, solar energy conversion, and molecular sensing

Photonic Weyl points due to broken time-reversal symmetry in magnetized semiconductor

Weyl points are discrete locations in the three-dimensional momentum space where two bands cross linearly with each other. They serve as the monopoles of Berry curvature in the momentum space, and their existence requires breaking of either time-reversal or inversion symmetry. Although various non-centrosymmetric Weyl systems have been reported, demonstration of Weyl degeneracies due to breaking of the time-reversal symmetry remains scarce and is limited to electronic systems. Here, we report the experimental observation of photonic Weyl degeneracies in a magnetized semiconductor—InSb, which behaves as a magnetized plasma19 for electromagnetic waves at the terahertz band. By varying the magnetic field strength, Weyl points and the corresponding photonic Fermi arcs have been demonstrated. Our observation establishes magnetized semiconductors as a reconfigurable terahertz Weyl system, which may prompt research on novel magnetic topological phenomena such as chiral Majorana-type edge states and zero modes in classic systems