Ultrahigh speed cryogenic laser diodes for broadband optical fiber link applications

In this paper, we present the first systematic study of the temperature dependence of the high performance of various laser diodes from room temperature down to 10 K. We found that as the threshold current of these diodes decreases by at least an order of magnitude at low temperatures, the modulation bandwidth is dramatically improved. The best result is 27 GHz at 100 K for an InGaAsP multiple quantum well laser. We also present experiments on a broadband optical fiber link utilizing a cooled laser diode as a transmitter for 10 Gb/s digital data transmission and 28 GHz carrier video delivery applications.<>