研究目的
Investigating the performance of Fabry-Perot quantum well lasers with shortened cavity designs (25 and 50 μm) for high-speed optical communication applications.
研究成果
We report the fabrication of ultra-short cavity semiconductor lasers with milliwatt-class output power. The fabricated devices with 25- and 50-μm cavities exhibited satisfactory high speed characteristics up to a temperature of 65oC and modulation speed of 25 Gb/s. An SMSR of more than 25 dB was obtained. Analysis indicated that a high internal loss value is associated with short-cavity devices, possibly due to a combination of process and cleaving variations. The modulation efficiencies were extracted from the current-dependent relaxation resonance frequency and were as high as 3.94 GHz/(mA)0.5. The scaling inspired by the small quantum well lasers will be important for future highly integrated photonic circuitry.
研究不足
The single-mode yield of such devices in the wafer is approximately 4%. When the device is modulated, the single mode is no longer present and the obtained optical spectrum is similar to that of a multiple mode laser.
