We theoretically analyzed the gain characteristics of an integrated semiconductor quantum dot (QD) fiber amplifier (SQDFA) by using a 2×2 tapered fiber coupler with a PbS QD-coated layer. The asymmetric structure of the fiber coupler is designed to have a maximum working bandwidth around 1550-nm band and provide a desired optical power ratio of the output signals. By using 600mW of 980-nm pump, 10dB gain of a 1550-nm signal is estimated with the gain efficiency of 4.5dB/cm.
- PbS QD-coated layer
- Semiconductor quantum dot (QD) fiber amplifier