New optical spiral technology can increase information transmission rate tenfold

A new optical-based communications tool can transmit data in rapid, cyclic motions, like an eddy current. The optical advance, described in a study published today in the journal Science, could be a core component of the next generation of computers that meet society's growing need to share information. It could also allay fears that Moore's Law -- the idea that researchers will find new ways to continually make computers smaller, faster and cheaper -- is running out.

For decades, researchers have been working to cram more components onto silicon-based computer chips than ever before. Their success explains why today’s smartphones have more computing power than the world’s largest computers of the 1980s, which cost millions of dollars in today’s money and were about the size of a large filing cabinet.

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But researchers are facing a bottleneck: existing technology can no longer meet society's demand for data. Although predictions vary, many believe this is likely to happen within the next five years. Researchers are tackling this problem in a variety of ways, including optical communications, which use light to transmit information. Examples of optical communications range from ancient lighthouses to modern fiber-optic cables used to watch TV and browse the Internet.

Lasers are the core components of today's optical communication systems. Researchers have manipulated lasers in various ways, the most common of which is to combine different signals into a single line to carry more information. But these techniques, especially wavelength division multiplexing and time division multiplexing, have also reached their limits.

The University at Buffalo-led research team used another light manipulation technique called orbital angular momentum to advance laser technology, which places the laser in a spiral pattern with a vortex at the center. Such lasers are usually too large for use in current computers, but the team succeeded in shrinking the vortex laser to a size comparable to a computer chip. Because the laser beam travels along a spiral pattern, the information is encoded into the different vortex curves, so it can carry ten times more information than a traditional laser that travels in a straight line.

Vortex lasers are just one of many components needed to build more powerful computers and data centers, which will ultimately require advanced transmitters and receivers.