Is It This Easy?

UC Berkeley-designed optoelectronic tweezers and optical conveyor belts bring technologies for aiding nano-assembly to the forefront.

In the design, the researchers reflect light from a digitally controlled array of mirrors, sending the light through a magnifying lens, and then into a sandwich of semiconductor planes, creating (at the interface between two of the planes) as many as 15,000 traps that can be addressed separately. In each of the traps, objects such as biological cells can be studied. Optoelectronic tweezers, which use optical energy to create powerful electric forces in carefully prescribed places, differ from ordinary optical tweezers, which use optical energy to create mechanical forces that can push things around, helping to make the technique potentially easier for laboratories to implement.

According to Berkeley's Aaron Ohta, the optoelectronic approach uses much less power than optical tweezers and doesn't need to be as carefully focused. In recent months the Berkeley group has had some success in using their locally controlled electric fields to manipulate the positions of tiny nanorods (100 nanometers in diameter and 1-50 microns long). The rods are suspended in a thin layer of water by sound waves and then transferred to the tweezer apparatus. Ohta says that the lateral-field optoelectronic device will possibly be used to place rods for the sake of building 3-D circuitry or for positioning oblong-shaped cells or cell protrusions with micron-level precision.

More images and movies at http://nanophotonics.eecs.berkeley.edu/.

Source

Combining these techniques with "self-assembly" techniques, as in these self-assembling batteries, should help nano-assembly along just a bit.

Researchers at MIT have designed a rechargeable lithium-ion battery that assembles itself out of microscopic materials. This could lead to ultrasmall power sources for sensors and micromachines the size of the head of a pin. It could also make it possible to pack battery materials in unused space inside electronic devices.

Technology Review

Nanotechnology is ages behind biological molecular assembly. But with computing technology advancing so quickly, an age can pass in the blink of an eye.