NSF, Vixar target 40-100 Gbps VCSEL

The National Science Foundation (NSF) has awarded Vixar a Small Business Innovation Research (SBIR) Phase I contract to demonstrate the feasibility of a composite resonator VCSEL (CRVCL) that can support a 40- to 100-Gbps serial data transmission rate. VCSELs have served as the primary optical transceiver light source for short distance (<300 meters) applications for more than a decade. However, the NSF and Vixar say that conventional VCSEL technology may top out at data rates between 20 and 30 Gbps. Straightforward design enhancement of conventional VCSELs will not satisfy the requirements, they believe. The CRVCL approach, for which Vixar has applied for a patent, avoids relaxation oscillation limitations on modulation speed through the use of a dual-cavity VCSEL operated in a push-pull configuration. The goals of the Phase I project are to fabricate such a CRVCL, demonstrate the push-pull nature of the modulation to a minimum of 20 GHz, and demonstrate the elimination or dramatic reduction in relaxation oscillations. At 40 Gbps and higher data rates, such a VCSEL would likely find application in SAN and high-performance computing, as well as use within optical interconnects within a cabinet or circuit board. These latter applications would require high speed per channel (at least 40 Gbps), very low power, high reliability, and low cost. Vixar believes the CRVCL could meet all four requirements. Vixar says it has already identified potential commercialization partners for the CRVCL.