Recent trends in photonics

Two topics in recent trends in photonics are highlighted, photonic crystals and silicon based optoelectronics. These trends aim at better, faster and cheaper communication via realizing low-cost optoelectronic functions. The idea is to combine the processing capabilities of electronics data transfer and the speed of light. This can be achieved by integration of photonic materials, where light can be generated, guided, modulated, amplified and detected, with standard electronic circuits. At the same time miniturization of such materials to perform the above functions is also thought of which the photonic crystals seems to offer a step on the way. To achieve the above goals; several strategies are thought through. Integration of photonic functions on one substrate is one, while hybrid integration of compound-semiconductor optical functions with Si electronic functions is another. A more ambitious strategy is to realize fully Si-based, or at least Si-compatible, optoelectronics. The main derive behind these goals are the developments of new materials and technologies. Erbium doped Si and SiGe, porous Si, and nanocrystals seems to enjoy the interest for such applications. In this article we address very briefly the main characteristics, advantages and shortcomings of these trends together with some of their successful applications