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nanotimes News in Brief

11-10 :: October 2011

Photonics // Microring Device Could Aid in Future Optical Technologies © Text: Emil Venere / Purdue

P

urdue University and the National Institute of Standards and Technology (NIST, both USA)

have created a device small enough to fit on a computer chip that converts continuous laser light into numerous ultrashort pulses, a technology that might have applications in more advanced sensors, communications systems and laboratory instruments.

“These pulses repeat at very high rates, correspondi- ng to hundreds of billions of pulses per second,” said Andrew Weiner, the Scifres Family Distinguished Professor of Electrical and Computer Engineering.

The tiny “microring resonator” is about 80µm, or the width of a human hair, and is fabricated from silicon nitride, which is compatible with silicon material widely used for electronics. Infrared light from a laser enters the chip through a single optical fiber and is directed by a structure called a waveguide into the microring.

The pulses have many segments corresponding to different frequencies, which are called „comb lines“ because they resemble teeth on a comb when repre- sented on a graph.

By precisely controlling the frequency combs, re- searchers hope to create advanced optical sensors

Researchers have created a tiny “microring resonator,” at left, small enough to fit on a computer chip. The device converts continuous laser light into numerous ultrashort pulses, a technology that might have appli- cations in more advanced sensors, communications systems and laboratory instruments.

At right is a grooved structure that holds an optical fiber leading into the device.

© Birck Nanotechnology Center, Purdue University