LETI: A New Approach to Store Data on a Silicon Ring Using Light Pulses

The effect that makes it possible to record information in a micro-ring resonator using light waves of different intensities opens up new opportunities for creating fast memory modules for computers of the future.

Today’s computers are approaching the limit of their capabilities in terms of performance to power consumption ratio. Therefore, research teams around the world are developing logic integrated circuits based on alternative principles that will be more compact, energy-efficient, and fast. One type of such circuit is the photonic integrated circuit, in which information is transmitted, stored, and processed using light.

“We have shown for the first time that stable nonlinear effects exist in micro-ring resonators with a diameter of about 0.2 mm, which make it possible to record data using optical waves. This was possible due to the bistability effect in this structure.”

Andrey Nikitin, Associate Professor of the Department of Physical Electronics and Technology at LETI
Silicon micro-ring resonators are manufactured according to the widespread silicon-on-insulator technology. Optical waves of different intensities are used to switch the output state: a low one encodes “0”, a high one – “1”. In this way, information is recorded. Experimental results, described in an article in the Optics Communications journal, showed that the system can stay in this state until the next information signal.

“This way, we get a very simple principle of operation, without the use of classical electronics. In the future, we plan to use this approach to create an optical memory cell. The combination of such cells is the basis for creating high-speed optical memory devices. Understanding such nonlinear effects is an important step toward creating photonic integrated circuits,” explains Andrey Nikitin.

The project is in line with many years of work of the Department of Physical Electronics and Technology on researching new physical effects in solids, which have great prospects for creating storage and processing devices. In 2020, LETI received a megagrant from the Government of the Russian Federation to carry out developments in the field of reservoir computing based on the principles of magnonics.