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A novel wavelength-division-multiplexed optical interconnect is demonstrated in which optical data from a monolithic wavelength-chirped VCSEL array is multiplexed onto a single fiber, and then demultiplexed using an array of wavelength-selective resonance-enhanced photodetectors with closely matched/resonance wavelengths. This is demonstrated under both DC and 125 Mb/s data modulation, achieving an optical crosstalk rejection ratio of /spl sim/-10 dB (-7.5 dB) for channels that are spaced 6 nm (4 nm) apart.

Optically cascadable and multifunctional binary optical switches consisting of AlGaAs-GaAs vertical cavity surface-emitting lasers (VCSELs), heterojunction bipolar transistors (HBTs), and p-i-n photodetectors (PINs) have been realized. Each switching element consists of a pair of PIN/HBT/VCSEL switches that can perform optical switching and routing at a data rate of 100 Mb/s, and optoelectronic signal conversion at a data rate of 100 Mb/s, while achieving a peak dc optical gain of 18 and an ac optical gain of 4. Optically-cascaded, multistage switching operation has been demonstrated using two linear arrays of HBT/PIN/VCSEL switches, with an overall cascaded dc optical gain of 50 and an ac gain of 8.

Monolithic wavelength-graded vertical-cavity surface- emitting laser (VCSEL) and wavelength-selective resonance enhanced photodetector (REPD) arrays have been developed for use in wavelength-division multiplexed optical interconnect architectures. The aim is to achieve a cost-effective wavelength-multiplexed optical interconnect that can carry a large amount of data over longer distances using a single optical fiber. A controllable means for producing wavelength-graded VCSEL and REPD arrays is described, based on the topography-controlled MOCVD growth on a patterned substrate. This technique allows the growth rate of all the epilayers to be scaled, thereby providing closer tracking of the reflectance peak and the gain peak and resulting in more uniform device characteristics. VCSELs and REPDs have been monolithically integrated using the same epilayer structure and the same growth technique. This paper focuses on (1) the characteristics of oxide-confined multi-wavelength VCSEL arrays, (2) the design and comparison of optimized REPD structures at 850 nm and at 980 nm, and (3) wavelength multiplexing and demultiplexing using VCSEL and REPD arrays.

Monolithic, uniformly-wavelength-graded, vertical-cavity surface- emitting laser (VCSEL) and wavelength-selective resonance- enhanced photodetector (REPD) arrays are key enabling technologies for many wavelength-multiplexed optical network and interconnect architectures. These arrays can be produced in a repeatable and uniform manner by controlling the local MOCVD growth rate of the epilayers on a topographically patterned substrate, which resulted in wavelength-differentiated devices with more uniform optical characteristics. Multi-wavelength VCSEL and REPD arrays have been monolithically integrated on the same substrate to improve the wavelength matching between the source and detector elements. The performance characteristics of these arrays are discussed. We also describe a wavelength-division- multiplexing and demultiplexing experiment in which several channels of optical data are multiplexed together using a multi- wavelength VCSEL array and transmitted on a single optical fiber, and are demultiplexed at the other end using a wavelength- selective REPD array with closely-matching wavelengths.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Recent advances in the design of high-speed optical switches and transceivers for a reconfigurable, spatially-multiplexed optical interconnection network are described. Monolithic switches based on the integration of vertical-cavity surface-emitting lasers with heterojunction bipolar transistors and photodetectors have achieved switching operation at a data rate of close to 1 Gb/s. Optical transmission experiments through fibers have been carried out using these switches at a data rate between 650 Mb/s and 1 Gb/s. For future improvements in performance, the photonic and electronic elements should be separately integrated and independently optimized. To facilitate photonic integration, VCSELs and resonance-enhanced photodetectors have been integrated on the same substrate.

We review our progress in the development of an optical interconnect technology consisting of optical and optoelectronic switches that integrate vertical-cavity surface-emitting lasers (VCSELs) with other photonic and electronic components, including heterojunction phototransistors (HPTs) and heterojunction bipolar transistors (HBTs). We describe a reconfigurable multi-access optical network architecture that allows many high speed electronic processors to simultaneously communicate with each other and with other shared resources, and for its implementation, an integrated optoelectronic switching technology that combines the functions of an optical transceiver and a spatial routing switch. The network provides parallel and dynamically reconfigurable optical interconnections between nodes, as well as optoelectronic interfaces to each processor. By converting data between the electrical and optical formats, these multi-functional switches can receive or transmit optical data, or to bypass and re-route it to another node. Optical switching has been demonstrated experimentally at a data rate of 200 Mb/s, and electrical-to-optical data conversion has been achieved at a data rate of > 500 Mb/s.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A cascadable binary optical routing switch with improved switching performance has been demonstrated by integrating vertical-cavity surface-emitting lasers with heterojunction bipolar transistors and pin photodiodes. The reconfigurable routing of optical signals, and their conversion between electrical and optical formats, have been achieved at high speed (400-500 Mbit/s), and with an optical gain of 7.5 dB.