Monolithic Multistage Optoelectronic Switch Circuit Routing 160 Gb/s Line-Rate Data

We propose, characterise and demonstrate a photonic multistage switching circuit operating at 160 Gb/s serial line rates. The circuit is realised on a re-grown active-passive wafer exploiting multiple stages of loss-compensating semiconductor optical amplifier crossbar switch elements. Excellent 40 dB crosstalk extinction is achieved, with signal to noise ratios of up to 39 dB/0.06 nm. Low loss circuit operation is presented, with the prospect of gain if antireflection coatings are applied at the input and output facet. Bit error rate studies show only modest levels of signal degradation under both static and dynamic operation. For static operation, power penalties of 0.6 dB and 1.2 dB are measured for two and four switch stages respectively. Dynamic switching is demonstrated with a power penalty of order 2.2 dB. The combined demonstration of a multistage monolithic photonic circuit and high line rate signal processing represents an important milestone towards ultrahigh data density optoelectronic signal processing.