"EMERGING TECHNOLOGIES" : This topic introduces u with various new and significant develepoments in diff fields of science n technolgy..

1. A New Focus For Light

" Kenneth Crozier and Federico Capasso have created light-focusing optical antennas that could lead to DVDs that hold hundreds of movies. "

Brief Description about the Technology

Researchers trying to make high-capacity DVDs, as well as more-powerful computer chips and higher-resolution optical microscopes, have for years run up against the "diffraction limit." The laws of physics dictate that the lenses used to direct light beams cannot focus them onto a spot whose diameter is less than half the light's wavelength.

Physicists have been able to get around the diffraction limit in the lab but the systems they've devised have been too fragile and complicated for practical use. Now Harvard University electrical engineers led by Kenneth Crozier and Federico Capasso have discovered a simple process that could bring the benefits of tightly focused light beams to commercial applications. By adding nanoscale "optical antennas" to a commercially available laser, Crozier and Capasso have focused infrared light onto a spot just 40 nanometers wide--one-twentieth the light's wavelength. Such optical antennas could one day make possible DVD-like discs that store 3.6 terabytes of data--the equivalent of more than 750 of today's 4.7-gigabyte recordable DVDs.