The CCSM has made key contributions in this area including development of the iPOINT optical interconnect testbed, link-level simulation, and experimental verification. The widely implemented impurity-induced layer disordering and native III-V oxide technologies for the fabrication of semiconductor lasers are both CCSM discoveries. CCSM researchers have made significant contributions to strained-layer quantum-well heterostructure lasers, quantum wire lasers, fabrication of photonic integrated circuits by selective-area epitaxy, and optical patterning of photosensitive glasses. Rare earth-doped chalcogenide glasses are being developed for application in planar thin-film and fiber based optical amplifiers and lasers. High-performance InP-based HEMT and MSM photoreceivers and carbon-doped HBTs trace their origins to work at the CCSM.
Advances made in this thrust will ultimately have applications in optical links, telecommunications, remote sensing, frequency conversion, WDM subsystems, bi-directional fiber to the home, and next-generation quality-of-service applications.
A cross section of an aluminum-gallium-arsenide quantum-well (QW)
heterostructure laser diode, this image (a) shows a 2.5 µm oxide-defined
pair of buried apertures created by CCSM researchers. When current is
applied to this device, it cannot penetrate the oxidized regions (layers
marked Ox), which provide a high degree of lateral optical confinement
in the QW active region.
The inset (b), a top view, shows that the oxidized region-oxidized from
the left and right edges‹appears translucent compared to the opaque
unoxidized 2.5 µm stripe.
This oxide technology has led to intensive research interest worldwide
and is the basis for research progress in one of the fastest-growing
areas of optoelectronics research: vertical-cavity surface-emitting
lasers (VCSELs). Some light-emitting diode (LED) and VCSEL products are
now being manufactured using this technology. CCSM researchers hold 12
patents relating to the oxide technology.
