Pixelated liquid-crystal light valve for neural network application.

The liquid-crystal light valve (LCLV) is a useful component for performing integration, thresholding, and gain functions in optical neural networks. Integration of the neural activation channels is implemented by pixelation of the LCLV, with use of a structured metallic layer between the photoconductor and the liquid-crystal layer. Measurements are presented for this type of valve, examples of which were prepared for two specific neural network implementations. The valve fabrication and measurement were carried out at the State Optical Institute, St. Petersburg, Russia, and the modeling and system applications were investigated at the Institute of Microtechnology, Neuchâtel, Switzerland.

Tubular graphite cones with single-crystal nanotips and their antioxygenic properties.

Tubular graphite cones (TGCs) with a single-crystal nanotip have been achieved by means of microwave plasma-assisted chemical vapor deposition using in-situ-evaporated Fe catalysts. The absence of the disorder-induced D band in Raman spectra revealed the single-crystalline feature of the nanotip. TGCs were found to stem from Fe catalytic carbon spherules on the order of 100 mum diameter, whose critical role in promoting both nucleation and plasma annealing in the formation of highly crystalline TGCs is discussed. The crystalline quality of such TGCs can be further verified by the investigation of their oxidative stability in air. All TGCs can survive up to 600 degrees C without any structural variations, and a few TGCs still survive with an anisotropic etched and stepped nanotip at temperatures up to 800 degrees C, much better than CNTs. Thus, TGCs with single crystalline nanotips are potential candidates for scanning probes in high-temperature oxygen-containing environments.