Abstract

High-speed optical fiber communication links require laser diodes operating at 1,55 pm with large modulation bandwidth. In most of these systems, the laser diodes are at or near room temperature. In some systems, such as space applications, the electrical and optical devices may be at cryogenic temperatures. Ultrahigh-speed superconducting integrated circuits require low thermal conductance, low cross talk noise, and high bandwidth interconnects to room temperature electronics. A high bandwidth cryogenic optical fiber link is an excellent candidate. Here we report a systematic study of the bandwidth of an optical fiber link with an InGaAsP quantum well laser diode as the transmitter at cryogenic temperatures. We found that as the laser diode was cooled from 300 K to 10 K, the threshold current was reduced from 25 mA to 1.2 mA. We also found that at temperature near 80 K, we achieved a modulation bandwidth of the optical fiber link exceeding 26 GHz.

© 1994 Optical Society of America