(iTers News) - IQE plc announces that vertical cavity surface emitting laser (VCSEL) devices using wafers produced at its Cardiff, UK facility have broken the 40 Gbit/s barrier at high temperatures. This is a key milestone in the adoption of photonic technologies for a wide range of data communications applications.
Optical communications provide the only reliable means of transferring the large volumes of data at ultra-high speeds needed in today’s data centres. The computing environments in which the data is transferred generally operate at elevated temperatures which make reliable operation at high temperature an essential element for the deployment of optical components.
A joint paper published by Chalmers University of Technology and IQE in IEEE Photonics Technology Letters (Vol. 25, No. 8, pp. 768-771, 2013), reports on the successful development of VCSEL devices operating at data rates of up to 47 Gbit/s at 25ºC and 40 Gbit/s at 85ºC.
VCSELs provide the primary light source for short-reach optical communication and currently provide the enabling technology for high capacity optical interconnect cables in storage area networks such as datacentres and server farms. VCSEL enabled, multimode fibre optic interconnects optimized for transmission speed at a wavelength of 850 nm are also used in high performance computing systems such as computer clusters and supercomputers.
Current high speed optical interconnects use VCSEL technology to operate at serial data rates of between 10-14 Gbit/s, with devices expected to perform at 25–28 Gbit/s under development. Next generation optical interconnect standards are expected to require data rates in excess of 40 Gbit/s. Such devices will be required to operate at the high ambient temperatures expected inside datacomms equipment.
The results were achieved at a modulation bandwidth of 27GHz at 25ºC and 21GHz at 85ºC, which is the highest for any VCSEL and the data rate is the highest of any VCSEL-based optical link without equalization. This is also the first 40 Gbit/s VCSEL operating at elevated temperatures, which is of utmost importance for practical applications.
The results also generated significant commercial interest when they were presented at the Optical Fiber Communication Conference (OFC) in Anaheim, California, last month.