采用变脊宽原理和对接生长技术,设计并制作了4通道分布反馈(DFB)激光器阵列与多模干涉(MMI)耦合器、半导体光放大器(SOA)的单片集成器件。在25℃的测试温度下,激光器的阈值电流约55-60mA;当激光器注入150mA、SOA注入50mA电流时,各通道的出光功率保持在2mw以上,出射波长处于1550nm波段,边模抑制比(SMSR)大于33dB,4通道可实现单独或同时工作。
The monolithic photonic integrated circuit (PIC) is the core component in the future high-capacity,low-power consumption optical network systems. As a typical photonics integrated device,monol ithically integrated multi-wavelength distributed feedback (DFB) laser array plays an important role in dense wavelength division multiplexing (DWDM) optical transmission systems. The monolithic integration of four distributed feedback lasers with a 4 × 1 multimode-interference (MMI) optical combiner and semiconductor optical amplifier (SOA) using varing width ridge method and butt-joint technology is proposed and demonstrated in this paper. The monolithically integrated chip is 2 500 μm long and 400 μm wide. The active and passive materials are integrated by the butt-joint technique,and the varing ridge width is used to adjust the effective index of the laser material, so that multi-wavelength emission can be achieved by normal holographic exposure. This method is simple and practical. The integrated device is tested at 25° for characterization. The average output power of 2 mW is achieved when the current of LD and semiconductor optical amplifier (SOA) is 150 mA and 50 mA,respectively. The threshold current of the device is 55--60 mA at 25 ℃. The lasing wavelength is around 1550 nm and more than 33 dB side mode suppression ratio (SMSR) is obtained. The four channels can operate separately or simultaneously.