We present a two-color (956 and 985 nm) InGaAs/AlGaAs laser structure epitaxially stacked through a low-resistance (10−5–10−4 Ω cm2) Esaki junction, exhibiting two threshold characteristics. It is shown that this structure can be considered as a bipolar cascade laser.

The design methodology, processing technology, and characterization of high-gain GaInP/GaAs heterojunctoin-bipolar-transistor-based distributed amplifiers are described in this paper. Distributed amplifiers with different active cells and number of stages have been compared for high-gain (>12 dB) and high-bandwidth (>25 GHz) performance. Based on the results, a three-stage attenuation-compensated distributed amplifier with a flat gain (S 21) of 12.7 dB over a bandwidth of 27.5 GHz was successfully fabricated and tested. Eye-diagram tests at 10 Gb/s show very open eye characteristics with no signal skewing. The amplifier achieves a minimum noise figure of 4 dB at 3 GHz and a sensitivity of 025 dBm for 10-Gb/s nonreturn-to-zero 2 15 0 1 pseudorandom bit sequence with a bit error rate of 10 09 .

No abstract

A self-aligned GaInF'/GaAs HBT technology was used to develop a monolithic high-gain transimpedance amplifier suitable for optical communication receivers. On-wafer probe measurements revealed a gain (SZJ of 18.8 dB with a bandwidth of 13.5 GHz and input, output matching better than -8 dB. The am lifier showed a sensitivity of -15 dBm for 10 Gb/s NRZ 2 -1 pseudo-random bit sequence with a BER ofThe noise figure of the amplifier was better than 7.5 dB over the bandwidth of operation.

No abstract