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Carbon nanotubes dispersed in ethanol are aligned by an electric field. Due to the orientation of these elongated particles, the dispersion exhibits anisotropic behaviour.Transmission experiments show rotation of the linear polarisation of an incident laser beam. Alignment and relaxation times and the influence of the magnitude of the electric field have been measured.

Measurements of the e + e~ cross section above BB threshold are reported. Structures are observed which could be the Y(5S) and Y(6S) resonances. The masses and widths are given and compared with various potential-model predictions. Average charged multiplicities and inclusive lepton yields are also presented.

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We report laser action in a Ti-diffused LiNbO(3) waveguide doped with trivalent Yb ions by thermal indiffusion. Lasing was observed at 1008, 1030, and 1060 nm with thresholds as low as 15-mW launched pump power. We reduced photorefractivity, which initially permitted only intermittent lasing, by annealing the sample in wet O(2). The annealed sample lased continuously in a cavity formed by high-ref lectivity mirrors; however, with a 7% output coupler the output power exhibited instabilities. The greatest value of the output power observed under these conditions was consistent with a slope efficiency of ~16% with respect to absorbed power.