iled and the design could then be modified," says St. John Dixon-Warren, a project coinvestigator and a physical chemist at Bookham Technology, an optical components manufacturer based in the United Kingdom. Sargent says the findings could have larger implications for the creation of optical circuits for fiber-optic communications. "If we could fully develop these models and fully understand how lasers work, then we could start to build optical circuits with confidence and high probability of success," he says. "Optical chips akin to electronic integrated circuits in computers must be founded on a deep and broad understanding of the processes at work inside current and future generations of lasers." 4.6.7 Manipulating Light Manipulating light on the nanoscale level can be a Herculean task, since the nanoscale level is SO incredibly tiny-less than one-tenth the wavelength of light. Researchers at Argonne National Laboratory are making strides toward understanding and manipulating light at the nanoscale level by using the unusual optical properties of metal nanoparticles, opening the door to micro- scopic-sized devices such as optical circuits and switches. Metal nanoparticles, such as extremely tiny spheres of silver or gold, can concentrate large amounts of light energy at their surfaces. The light energy confined near the surface is known as the near field, whereas ordinary light is known as far field. Many scientists believe that, by understanding how to OPTICAL ANTENNA manipulate near-field light, new optical devices could be built at dimensions far smaller than is currently possible. In an effort to characterize near-field behavior, a joint experimental and theoretical study published in the Decem- ber 25, 2003, issue of the Journal of Physical Chemistry B used powerful high- resolution imaging and modeling techniques to detail how light is localized and scattered by metal nanoparticles. Technologies, such as high-speed computers and internet routers, rely heavily on electrons flowing through wires to functio