Lithium niobate crystals are commonly used to encode data signals onto a lightwave carrier for telecommunications. But at extremely high speeds, these signals decay and are no longer useful for data transmission. Mark Lee and his colleagues at Bell Laboratories and Lucent Technologies fabricated a polymer "sandwich" containing a gold microstrip that was surrounded by glass. The team reports that careful selection of the materials can minimize signal interference; in test runs, their set-up detected a signal at 1,600 GHz. Although questions about the long-term reliability of such polymer devices remain, the scientists point out that they could be manufactured at lower costs than those in use today. "The ability to support extremely broad bandwidth operation, together with the possibility of low operating voltages," the authors conclude, "makes it plausible that an ultrafast polymer modulator with truly practical characteristics can be fabricated in the near future."
Anyone who has waited for a web page to download can appreciate the limitations of data transfer. Advances in fiber optics have already radically increased the Internet's speed since its inception, with bandwidths of 10 gigahertz (GHz), or 10 billion bits per second, common today. Now scientists have designed polymer devices that could dramatically improve the transfer of extremely large files. According to a report published today in the journal Science, the new design can supply a bandwidth of nearly 200 GHz.