Photonics

We study nonlinear effects in semiconductor lasers from the fundamental and applied points of view. Our research includes both experimental and theoretical studies of those systems. Our research is mainly focused on the nonlinear behavior of semiconductor lasers, in particular when they are subject to light emitted by another laser (optical injection) or by the same laser (optical feedback). Our aim is to use these systems to perform high-speed signal processing. At the present time we work in the following two research projects:

ALAS PROJECT

In this project we are interested in an special type of semiconductor laser, the vertical-cavity surface-emitting laser (VCSEL). This laser is an example of microlaser (with micrometric dimensions). Nowadays VCSELs are used as emitters in local area networks, in optical interconnections, optical mice, sensors... We are interested in a better understanding of the characteristics of the light emitted by those devices, not only  in their solitary operation, but also when they are subject to optical injection or optical feedback.

Experiments are done in the Optical Communications Lab of the Instituto de Física de Cantabria. We study how fast changes of the polarization or the transverse modes emitted by the VCSEL when it is subject to optical injection can be utilized to get several functionalities of all-optical signal processing: optical memories, inversion and regeneration of the signal. High-speed all-optical signal processing is of great interest for future applications in computing or in optical communication systems. 

PHOCUS PROJECT

The aim of the European project PHOCUS (Towards a photonic liquid state machine based on delay-coupled systems) is the study of a novel photonic system able to process information in an efficient and fast way. The basic idea is to use semiconductor lasers subject to delayed feedback to generate a high-dimension space. In this way we pretend to substitute the neural networks based on hundred of components by a small number of coupled photonic components. This photonic system will permit high-speed information processing (in the MHz-GHz range).