We report on a simple and universal method for fabricating various kinds of metal and semiconductor (Si, Ge, Bi, and Cu) nanoparticleÀglass composites by using metallic Al as a reducing agent in the raw materials of the glass batches. By taking advantage of the redox equilibrium that sets up between the Al reducing agent and various oxides, crystal nuclei such as Si and Ge atom clusters are already formed during the meltquenching stage. During the subsequent heat-treatment stage, the nanoparticles grow on the nuclei by a process of diffusion. The nanoparticle size can be controlled by heat-treatment temperature and holding time. The fabricated nanoparticleÀ glass composites exhibit large third-order optical nonlinearities (χ 3 up to 10 À8 esu) and an ultrafast response time (within picoseconds), which makes them possible to manufacture ultrafast alloptical switches.

We report the formation of inverted microstructures inside glasses after femtosecond laser irradiation by tuning the refractive index contrast between the immersion liquid and the glass sample. By using water as well as 1-bromonaphthalene as immersion liquids, microstructures with similar shape but opposite directions are induced after femtosecond laser irradiation. Interestingly, the elemental distribution in the induced structures is also inverted. The simulation of laser intensity distribution along the laser propagation direction indicates that the interfacial spherical aberration effect is responsible for the inversion of microstructures and elemental distribution.

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By combing laser direct writing and hydrothermal growth, we demonstrate the growth of three-dimensional flowerlike ZnO nanostructures from aqueous solution. Our approach offers synthetic flexibility in controlling film architecture, coating texture and crystallite size. The wettability is studied by measurement of time-dependent contact angles in the as-grown samples. In addition, superior photocatalytic activity of the flowerlike ZnO nanostructures in the degradation of Rhodamine B is investigated as well. The influence factors and formation mechanism of the flowerlike ZnO nanostructures are also analyzed and discussed.

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