RESUMO
The first ultracompact transmitter optical subassembly for long-distance, beyond-100-Gbit/s data communication systems based on a monolithically integrated light source is developed. The light source consists of four InGaAlAs-based electroabsorption modulator integrated DFB lasers (EADFB lasers) and their optical multiplexer and these components are monolithically integrated on one chip, resulting in very small chip size of 2.4 × 3.3 mm2. This small chip makes it possible to reduce the size of the transmitter module. Very small transmitter optical subassemblies (TOSAs), using the chip and employing three-dimensional interconnection board, is fabricated, whose volume is only 1.82 cc. By using the TOSA, 40-Gbit/s × 4 operation with the clear eye openings up to 10-km single mode fibre transmission is demonstrated. Electrical crosstalk under the multi-lane operation is also evaluated, and the error-free transmission is achieved with the power penalty to the discrete operation of 1 dB.
RESUMO
We present a novel parallel-ring-resonator tunable laser monolithically integrated with an InGaAlAs electroabsorption modulator. The fabricated tunable laser exhibits stable wavelength tuning with a step of 200 GHz over a wide tuning range of 35 nm, achieved with a single electrode control. The variation in the laser output power with wavelength tuning is less than 1 dB even at an injected tuning current of 20 mA. Clear eye openings at 25 Gbit/s with a dynamic extinction ratio of more than 10 dB are demonstrated over a wavelength range of 25.7 nm with a constant voltage swing of 2 V at 45 °C. Error-free operation is confirmed under the same operating conditions.
