On December 2, foreign expert Amer Kotb from the GPL Photonics Laboratory of CIOMP gave a talk entitled "Carrier reservoir semiconductor optical amplifiers (SOAs)-based logic gates". The International Cooperation Office of CIOMP and the GPL Photonics Laboratory sent invitations to all employees and students of the institute to attend Amer’s talk.

Dr. Amer Kotb is an associate professor at Fayoum University in Egypt and also an associate professor at the GPL Photonics Laboratory of CIOMP. His research mainly focuses on all-optical optical logic gates using different optical waveguides such as SOAs, quantum dots, phonic crystals, metasurfaces, etc. Over the years of related research work, 55 influential peer-reviewed papers and 2 monographs have been published. In addition, he has served as a reviewer for several journals, including Optics Letters, IEEE Transactions on Microwave Theory and Techniques, IEEE Photonics Journal, Optics and Laser Technology, Optics Communications, etc. Moreover, he served as a member of the editorial board of The American Association for Science and Technology (AASCIT) and Journal of Communications and Software. Since 2010, Dr. Amer Kotb has received the International Publication Award from Fayoum University in Egypt almost every year. He was also awarded the Best Young Scientist Award by Northern Borders University in Saudi Arabia.

In this talk, Dr. Amer Kotb talks about the CR-SOA and how to use it in implementing all-optical logic gates at a higher speed. It is known that the conventional bulk SOA faces the problem of the slow gain recovery time, which limits its application as a nonlinear element at higher data rates. Therefore, our goal is to find an alternative that works at higher rates with acceptable performance. Therefore, we employ, for the first time, a CR-SOA to execute all-optical Boolean operations at a data rate of 120 Gb/s. A performance comparison between the CR-SOA and the conventional bulk SOA is made by studying the variation of the quality factor (Q-factor) against various key operating parameters, including but not limited to the transition time from the carrier reservoir to the active region, the population inversion factor, the injection current, the equivalent pseudorandom binary sequence length, the alpha-factor, the optical confinement factor, the operating data rate, the input pulse energy, and the continuous wave power. The impact of the amplified spontaneous emission noise is taken into account for more realistic results. The obtained results demonstrate that owing to the CR-SOA’s faster gain and phase recovery, the CR-SOA is more suitable for realizing the logic gates at 120 Gb/s as it manages to achieve a more than acceptable Q-factor.

After the talk, participants had a warm discussion with Dr. Kotb. In the future, the International Cooperation Office will hold more CHANGGUANG International Forums to speed up the international process of CIOMP.