Chaotic dimension enhancement by optical injection into a semiconductor laser under feedback

Optical injection into a chaotic laser under feedback is investigated for dimension enhancement. Although injecting a solitary laser is known to be low-dimensional, injecting the laser under feedback is found to enhance the correlation dimension D-2 in experiments. Using an exceptionally large data size with a very large reconstruction embedding dimension, efficient computation is enabled by averaging over many short segments to carefully estimate D-2. The dimension enhancement can be achieved together with time-delay signature suppression. The enhancement of D-2 as a fundamental geometric quantifier of attractors is useful in applications of chaos. (C) 2022 Optical Society of America