Semiconductor optical amplifier (SOA) integrated on a silicon photonic chip using photonic wire bonds (PWBs)

Abstract

In this paper, we demonstrate near-C-band semiconductor optical amplifiers (SOAs) integrated on silicon photonic chips using photonic wire bonds (PWBs). PWBs are three-dimensional, nano-printed, freeform, polymer waveguides which provide efficient coupling between optical components. The SOAs used in this work were 975µm long and 400µm wide, with a 1.54µm wide, 1.9µm thick active region. Measurements on a connectorized SOA are presented, showing a peak on-chip gain of 10.6dB at 1510nm when applying a 150mA bias current to it (here we have not calibrated out the coupling losses at the two SOI-waveguide/PWB interfaces nor have we calibrated out the losses at the two PWB/SOA interfaces, indicating that the gain of the SOA is significantly higher than the measured 10.6dB). The PWBconnectorized SOA has a wavelength-dependent gain which was measured from 1480nm to 1555nm, the peak gain being obtained at 1510nm. In addition, the gain depends on the bias current applied, increasing with higher bias currents but saturating when the bias current exceeds 150mA. The PWB-connectorized SOA is also sensitive to the power of the input signal, the gain was larger for lower input powers (i.e., for powers below about -4.9dBm). Varying the polarization state of the input to our PWB-connectorized SOA changed the measured gain by 5.85dB.