New Organic Polymers to Replace Crystalline Optical Materials

Monday, December 01 2008

Development of a novel polymer, funded by the Missile Defense Agency (MDA) and other agencies, has opened the door to faster and more reliable switching in optical communications, with implications for numerous optical technology applications.

These polymers, known as electro-optic (E/O) polymers, are imbued with light-absorbing molecules called chromophores, which are found in nature in substances like chlorophyll and beta-carotene. The chromophores convert light into electrical current with high efficiency. E/O polymers have been known for some time to have the potential to outdo slower inorganic materials like gallium arsenide and lithium niobate. There are many applications for E/O polymers, including radio frequency, microwave, and millimeter-wave power distribution; phasedarray radar; photonic detection of electromagnetic radiation (such as radar signals); remote voltage sensing; flat-panel display modulators; and ultrafast analog-to-digital converters.

Offered by Lumera Corp. of Bothell, WA, electro-optic polymers have the potential for terahertz operational frequencies — two to three orders of magnitude beyond the capabilities of materials now available. These polymers can take the place of traditional crystalline materials such as lithium niobate, which is used in optical communications waveguides, switches, and modulators — devices that help route the light waves in optical communications.

The polymers were originally developed through an academic project, with funding from MDA predecessor BMDO. Beginning in the early 1990s, Professor Larry Dalton and colleagues oversaw a concerted effort to develop novel electrooptic polymers at the University of Southern California’s Loker Hydrocarbon Research Institute. BMDO provided funding for this effort on the strength of its interest in radar, telecommunications, and remote-sensing technologies. Dalton’s efforts in stabilizing and integrating the polymers into optoelectronic systems paved the way for Lumera to offer compact, high-bandwidth, optical communications links in a small space with very low losses, something that manufacturers of lithium-niobate-based modulators cannot hope to match.