高增益偏振不灵敏InGaAs/InP体材料半导体光放大器

采用三元InGaAs体材料为有源区，通过直接在InGaAs体材料中引入0．20％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0．5dB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1．1dB的偏振灵敏度。对于1．55gm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。

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

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.