Boost for Optical Data Transmission

A special kind of atomic layer deposition helps to create nanosized amplifier for optical propagation of data inside a microchip. (Source: A. Matikainen, Aalto U.)

Light is a more energy efficient and faster way of trans­ferring data than elec­tricity. Until now, the rapid attenua­tion of light signals in microchips has prevented the use of light as a source of an information signal. With inter­national colla­boration, researchers at Aalto University have now developed a nanosized amplifier to help light signals propagate through microchips. Now, the researchers show that signal atte­nuation can be signi­ficantly reduced when data is transferred inside a microchip, for example, from one processor to another.

“Photonics, or light transfer that is already widely used in internet connections, is increa­singly being used by micro­circuit systems because light is a more energy efficient and faster way of transferring data than elec­tricity. The increase in infor­mation also requires an increase in performance. Boosting per­formance through electronic methods is getting to be very difficult, which is why we’re looking towards photonics for answers,” says doctoral candidate John Rönn. The researchers made their break­through with the help of a Finnish invention: the atomic layer deposition method. According to the team, the method is ideal for processing various kinds of micro­circuits, as it plays an important role in manu­facturing today’s micro­processors.

So far, the atomic layer deposition method has been used mainly in electronic appli­cations. However, the newly released study indicates that possible appli­cations also exist in photonics. In the development of photonics, new components must also ideally work with elec­tricity in electronics. “Silicon is a key material in elec­tronics, and that’s why it’s also included in our light amplifiers together with the ampli­fication element erbium,” Rönn says. “Today’s compound semi­conductors, which are used, for instance, in LED tech­nology, can also be used effec­tively in light ampli­fication. That being said, most compound semi­conductors are not compatible with silicon, which is a problem for mass production.”

The researchers showed that a light signal can be potentially boosted in all kinds of structures and that the structure of a microchip is not limited to a specific type. The results indicate that atomic layer depo­sition is a promising method for deve­loping microchip photonic processes. “Our inter­national colla­boration made a break­through with one component: a nanosized amplifier. The ampli­fication that we got was very signi­ficant. But we’ll still need more components before light can completely replace elec­tricity in data transfer systems. The first possible appli­cations are in nano­lasers, and in sending and amplifying data,” says Zhipei Sun. (Source: Aalto U.)

Reference: J. Rönn et al.: Ultra-high on-chip optical gain in erbium-based hybrid slot waveguides, Nat. Commun. 10, 432 (2019); DOI: 10.1038/s41467-019-08369-w

Link: Dept. of Electronics and Nanoengineering, Aalto University, Espoo, Finland

Speak Your Mind