High-Power, Narrow-Linewidth, and Low-Noise Quantum Dot Distributed Feedback Lasers

Single-frequency semiconductor lasers represent a critical role in optical communications, light detection and ranging systems, photonics integrated circuits, etc. Here, combining atom-like quantum dot (QD) materials and advanced lateral gratings, a high-power, ultra-low-noise 1.3 & mu;m InAs/GaAs QD distributed feedback laser is demonstrated. Stable single-longitudinal-mode output power of 100 mW from 25 celcius to 85 celcius is achieved with a maximum side mode suppression ratio of 62.6 dB, and the variations of threshold current and slope efficiency over the temperature range are slight, indicting a high temperature stability. A record-narrow intrinsic linewidth of 1.62 kHz is achieved at 55 celcius with a white noise level of merely 515 Hz(2) Hz(-1), and a minimum averaged relative intensity noise of only -166 dB/Hz between 0.1 GHz and 20 GHz is obtained at 25 celcius. Furthermore, a strong tolerance to external optical feedback (& rang; -14 dB) is demonstrated in the range from 25 celcius to 85 celcius, with a maximum value of -8 dB at 85 celcius. This high-quality single-frequency laser fabricated with simplified processes and compact size paves the way for its future large-scale applications such as high-capacity optical communication, high-precision optical detection, high-speed optical interconnections, etc.