Dual-mode semiconductor lasers in reservoir computing

Delay-based reservoir computing schemes using semiconductor lasers have proven robustness and good performances for a wide range of tasks. These schemes are especially desirable because of their inherent high speed in data processing and the promise of miniaturization. One such scheme is based on a single-mode semiconductor laser subjected to optical feedback, which can be designed for on-chip implementation. However, the feedback line length remains to be a limiting factor in the miniaturization process. We propose to target more than one mode in a semiconductor lasers. In this way, we believe that it would be possible to distribute the computational power over several modes. Also, having more optical modes addressable will allow for a larger variability and parameter space both at the input and output layers of the reservoir computer. The complex interactions between either optical mode and optical mode or optical mode and carrier densities introduce new dynamical features, as well as increase the available nonlinearity in the system. We envision multiple mode reservoir computing as the next crucial step in optical reservoir computing evolution.