It's a small (very small) world

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Nanotechnology is developing at a pace that makes many sci-fi scenarios outdated almost daily. This time, I'd like to report about tools and light.

Carbon nanotubes are incredibly strong. They can resist to pressures as high as 40 gigapascals (ca. a tenth of the one at the center of the Earth). They have now been used to create metalworking tools (nanoscale jigs or extruders, see picture on the right). This could become an alternative way to manipulatating structures at the nanoscale. You could build them as you build a table. (Science, "Carbon Nanotubes as High-Pressure Cylinders and Nanoextruders" Vol. 312, No. 5777, pages 1199 - 1202).

So, fancy building a nanoship in a nanobottle?

Well, if your objection to the exercise is that it is too dark down there for anyone to appreciate your work of art, it's time to cheer up. It is now possible to grow glowing nanowires to light up the nanoworld. Nanowires made of semiconductor materials can now be used to build prototype lasers and light-emitting diodes with emission apertures roughly 100 nm in diameter. The wires are generally between 30 and 500 nanometers (nm) in diameter and up to 12 micrometers long (see picture on the right). When excited with a laser or electric current, the wires emit an intense glow in the ultraviolet or visible parts of the spectrum, depending on the alloy composition. (J.B. Schlager, N.A. Sanford, K.A. Bertness, J.M. Barker, A. Roshko and P.T. Blanchard. 2006. Polarization-resolved photoluminescence study of individual GaN nanowires grown by catalyst-free MBE. Applied Physics Letters. May 22. K.A. Bertness, N.A. Sanford, J.M. Barker, J.B. Schlager, A. Roshko, A.V. Davydov and I. Levin. 2006. Catalyst-Free Growth of GaN Nanowires. Journal of Electronic Materials 35, 576. April).

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