THE highest resolution optical image yet taken has been snapped at a lab in New York.
Achim Hartschuh and Lukas Novotny at the University of Rochester have found a way to examine carbon nanotubes with red light, although the tubes are many times thinner than the wavelength of light used in the experiments. The trick is to focus a light beam onto the tip of an extremely fine silver wire 1 nanometre above the nanotubes, creating a strong electromagnetic field. The nanotubes absorb energy from the field, and emit it back at a wavelength which can then be recorded by an extremely sensitive photon detector.
Hartschuh and Novotny have seen details on the nanotubes as small as 25 nanometres, about 1/25th the 633-nanometre wavelength of the red laser beam, they report in Physical Review Letters (vol 90, p 095503). They say the technique could be extended to examine and identify proteins.
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