Center for Subwavelength Optics and Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Korea.
Published: August 2010
AI Article Synopsis
Article Abstract
We report on an order of magnitude enhanced nonlinear response of vanadium dioxide thin film patterned with nanoresonators--nano slot antennas fabricated on the gold film. Transmission of terahertz radiation, little affected by an optical pumping for the case of bulk thin film, can now be completely switched-off: DeltaT/T approximately -0.9999 by the same optical pumping power. This unprecedentedly large optical pump-terahertz probe nonlinearity originates from the insulator-to-metal phase transition drastically reducing the antenna cross sections of the nanoresonators. Our scheme enables nanoscale-thin film technology to be used for all-optical switching of long wavelength light.
Mastering the surface chemistry of quantum dots (QDs) has enabled a remarkable gas-sensing response as well as impressive air stability. To overcome the intrinsic receptor-transducer mismatch of QDs, PbS QDs used as sensitive NO receptors are spin-coated on top of a few-layer MoS and incorporated into a thin-film transistor (TFT) gas sensor. This architecture enables the separation of the electron transduction function from the chemical reception function.
In recent years, single-atom catalysts (SACs) with separated active centers and high atom utilization have grown significantly as a significant area of catalytic research. In catalytic applications, SACs of various kinds have demonstrated exceptional performance, so the study of the catalytic mechanism of SACs provides a clearer direction for the preparation of catalysts with high performance. Strong linkages between the single atoms and the support are necessary to overcome the tendency of single atoms to aggregate into clusters, which is called metal-support interaction (MSI).
We demonstrate a hybrid integrated optical frequency comb amplifier composed of a silicon carbide microcomb and a lithium niobate waveguide amplifier, which generates a 10-dB on-chip gain for the C+L band microcombs under 1480-nm laser pumping and an 8-dB gain under 980-nm laser pumping. It will solve the problem of low output power of microcombs and can be applied in various scenarios such as optical communication, lidar, optical computing, astronomical detection, atomic clocks, and more.
With the increasing demand for food safety monitoring, the development of efficient, convenient, and green gas sensors has become a current research hotspot. Triboelectric nanogenerator (TENG) as a triethylamine sensor is a cutting-edge strategy for detection without the need for an additional power source. In this study, synthesized WO/MXene materials were prepared and bilayer thin films of carbon quantum dots (CPDs)-WO/MXene TENG.
The high potential of non-covalent arene-fluoroarene intermolecular interactions in the design of liquid crystals lies in their ability to strongly promote self-assembly, improve the order and stability of the supramolecular mesophases, and enable tuneability of the optical and electronic properties, which can potentially be exploited for advanced applications in display technologies, photonic devices, sensors, and organic electronics. We recently successfully reported the straightforward synthesis of several mesogens containing four lateral aliphatic chains and derived from the classical triphenylene core self-assembling in columnar mesophases based on this paradigm. These mesogenic compounds were simply obtained in good yields by the nucleophilic substitution (SFAr) of various types of commercially available fluoroarenes with the electrophilic organolithium derivatives 2,2'-dilithio-4,4',5,5'-tetraalkoxy-1,1'-biphenyl (2Li- ).
