高增益偏振不灵敏InGaAs/InP体材料半导体光放大器

High-Gain Polarization-Insensitive Semiconductor Optical Amplifier with Tensile-Strained InGaAs/InP Bulk Material

采用三元InGaAs体材料为有源区,通过直接在InGaAs体材料中引入020%张应变来加强TM模的增益,研制了一种适合于作波长变换器的偏振不灵敏半导体光放大器(SOA)。在低压金属有机化学气相外延(LPMOVPE)的过程中,只需调节三甲基Ga的源流量便可获得所要求的张应变量。制作的半导体光放大器在200mA的注入电流下,获得了50nm宽的3dB光带宽和小于05dB的增益抖动;重要的是,半导体光放大器能在较大的电流和波长范围里实现小于11dB的偏振灵敏度。对于155μm波长的信号光,在200mA的偏置下,其偏振灵敏度小于1dB,同时获得了大于14dB光纤到光纤的增益,3dBm的饱和输出功率和大于30dB的芯片增益。用作波长变换器,可获得较高的波长变换效率。进一步提高半导体光放大器与光纤的耦合效率,可得到性能更佳的半导体光放大器。

Ternary InGaAs bulk layer is used as active region. TM mode gain is enhanced by directly introducing 0.20% tensile strain into bulk InGaAs active layer so that a polarization insensitive semiconductor optical amplifier (SOA) for converter is fabricated. The desired tensile strain value is achieved by only changing the TMGa source flow during low pressure metalorganic vapor phase epitaxy (LP MOVPE). At injection current of 200 mA, the fabricated SOA has a 3 dB optical bandwidth of 50 nm and the gain ripple is less than 0.5 dB. More important is that the polarization sensitivity of SOA is less than 1.1 dB over a wide current and wavelength range. Under bias of current of 200 mA, for λ=1.55 μm, the SOA shows less than 1 dB polarization sensitivity, 14 dB fiber to fiber gain, 3 dBm saturation output power and more than 30 dB chip gain. A high conversion efficiency can be obtained when SOA is used as wavelength converter. A better performance SOA will be achieved if the coupling loss between the SOA chip and the fiber is decreased further.