Fabrication and characterization of 1 550 nm polarization-insensitive semiconductor optical amplifiers

摘要

A 1 550 nm polarization-insensitive semiconductor optical amplifier (SOA) was fabricated with InGaAs tensile-strained bulk active region.Beam propagation method and planar wave expansion method are used to calculate the mode field profile and the mode reflectivity.For the SOA with a buried waveguide deviated 7° from the normal direction of cleaved mirrors,the thickness tolerance of the mirror is 3% for keeping the reflectivity of TE mode and TM mode less than 10 -4 simultaneously.For a SOA with a cavity length of 800 μm,the polarization sensitivity of amplified spontaneous emission spectra is less than 0.5 dB at an injection current of 250 mA,the corresponding fiber-to-fiber gain is 11.9 dB at 1 550 nm with a 3 dB bandwidth of 63 nm ,and the saturation output power is 5.6 dBm .The noise figure shows 8.8 and 7.8 dB at 1 550 and 1 570 nm,respectively.For a packaged SOA with a cavity length of 1 000 μm,the fiber-to-fiber gain is 15 dB at an injection current of 190 mA.