Intermixed quantum well structures created by both impurity- induced and impurity-free or vacancy-promoted processes have recently attracted much attention. The full integration of photonics devices like tunable lasers, modulators and photodetectors has been attained and can be obtained using the quantum well intermixing technology. The advantage of being able to tune the material properties allows the realization of higher-performance devices, such as lasers, photodetectors and modulators. This bandgap modification is a powerful technique for monolithically integrating optoelectronic devices of varying functionalities on a single wafer. This paper will explore the wavelength tunability using different quantum well intermixing techniques. In addition, this paper will place a strong emphasis on the very recent device applications of intermixing technology. Attractive distributed-feedback laser and modulators have been developed as a result of some unique devices of quantum well intermixing. In particular, this allows a multi-section integrated structure to be fabricated for wide band-width and multi-wavelength applications. The use of such structure in wavelength division multiplexing (WDM) in high bit rate communication systems is a good example. Several state-of-the-art results of the intermixed quantum wells will be summarized, with an emphasis on the directions for future development.
|