High extinction ratio and high-temperature 2.5-Gb/s floor-free 1.3-mu m transmission with a directly modulated quantum dot laser

For the first time with a directly modulated InAs-GaAs quantum-dot laser, high extinction ratio (up to 17 dB) and 25 degrees C-85 degrees C single-mode-fiber data floor-free transmissions are achieved at 2.5 Gb/s. Moreover, an interferometric technique showed a nearly constant Henry factor similar to 2 until a bias current six times the threshold current.