Extremely broadband InGaAsP/InP superluminescent diodes

Broadband characteristics are attractive for optical fiber communication. Recent technology has made optical fiber exhibits very broad bandwidths, almost covering the range from 1200 to 1600 nm with a loss of less than 1 dB/km. However, to cover the entire usable bandwidth of an optical fiber, many conventional SLDs having different spectral range are required because each conventional SLD usually has a bandwidth of less than 50 nm. Therefore, if the bandwidth of SLDs could be broadened, they will be even more attractive. SLDs. Multiple quantum well (MQW) is a convenient way that has been widely used to broaden the bandwidth of SLDs.[1] However the design is not straightforward because the carrier distribution within the MQW is not uniform.[2] By considering the uniform carrier distribution within MQWs, we demonstrate that the spectral bandwidth of SLDs can be significantly broadened by using properly designed non-identical MQWs grown on InP substrate.