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We present a complete characterization of reflective electroabsorption modulators (EAMs) monolithically integrated with semiconductor optical amplifiers (SOAs), components that are capable of operating beyond 50 Gb/s in the C-band. The devices are based on GaInAsP multiple quantum wells on InP substrate, leveraging semi-insulating buried heterostructure waveguide definition and butt-joint integration technologies. Different device configurations, based on 80- and 150-μm long EAMs, are fabricated and characterized in both static and dynamic modes. The frequency response of the 80 μm long EAM is still flat at 26.5 GHz (setup upper limit) whereas the 150 μm long EAM exhibits a 3-dB cutoff bandwidth of 23 GHz. A zero-chirp is achieved for EAM reverse bias voltages between −1.2 and –1.5 V depending on the wavelength. Under large-signal modulation, the frequency chirp induced by the shorter EAM is almost half that of the longer EAM, with their respective peak values being +1.5/−2 and +3.2/−3.7 GHz (rising/falling edges) at 1545 nm (−1.3 V bias, 2.6 V voltage swing). We obtained high dynamic extinction ratios of ∼14.5 and ∼8 dB from the longer and the shorter EAMs, respectively, when they are operated at 25 Gb/s using non-return-to-zero coding. Finally, we achieved 12 and 16 km colorless transmissions in the C-band (between 1530 and 1545 nm) over a standard single-mode fiber without equalization using the 150- and the 80 μm EAMs, respectively, with 4.5 and 2.5 dB dispersion penalties at a bit error rate of 10–3. [ABSTRACT FROM AUTHOR]

We report on an ultrahigh-speed PAM-based IM/DD optical subsystem featuring compact signal generation and tractable digital-processing complexity. The proposed transceiver is based on two main technologies: an InP DHBT selector power DAC for electrical signal generation, and a complexity-optimized receiver processing chain. We show how the complexity of the feed-forward equalizer can be considerably reduced by stacking a <3-symbol memory sequence estimator. Finally, we experimentally demonstrate successful signal recovery for 107-GBd PAM-4 in back-to-back configuration, and after 500 m and 1 km of transmission over standard single-mode fiber for 100- and 84-GBd PAM-4 configuration, respectively. A power-budget margin above 2 dB is attained in all cases. [ABSTRACT FROM PUBLISHER]

We report a cost-effective 40-Gb/s time-division multiplexing passive optical network downstream link using three-level electrical duobinary modulation. The transmitter consists ofa compact electroabsorption-modulated laser module. The receiver contains an avalanche photodiode packaged with a transimpedance amplifier, with digitally adjustable gain and bandwidth, followed by a duobinary decoder. Real-time eye diagram and bit-error rate (BER) measurements were performed. At a preforward error correction BER of 10-3, a power budget of 23.6 dB in back-to-back conditions is demonstrated. For a dispersion range of -215 to 128 ps/nm, the power penalty does not exceed 3 dB. [ABSTRACT FROM PUBLISHER]

The future technology migration in access networks compels the development of key innovative transmitters operating at 10 Gb/s around 1550 nm and capable of transmitting data in extended reach passive optical networks (>60 km). A laser modulated directly appears to be a low cost and a simple solution to address these needs. However, the extinction ratio and the distance of transmission are limited by frequency chirping inherent to high bit rate modulation at 1550 nm. In this letter, we demonstrate the monolithic integration of a directly modulated lasers and a ring resonator (RR) and show the possibility to engineer the RR with specific frequency modulation efficiency. The ring is used as an optical eye reshaper, which enables the increase of the extinction ratio above 9 dB. Transmissions up to 65 km with 5.8 dBm of modulated optical power coupled into the fiber are demonstrated, proving the feasibility of our transmitter for the next generation passive optical network stage 2. [ABSTRACT FROM PUBLISHER]

We demonstrate a 56-GBd pulse-amplitude modulation-4 compact InP transmitter module integrating a distributed feedback laser and an electro-absorption modulator, which exhibits 50-GHz bandwidth, >13-dB extinction ratio and up to 1.5-mW output power. Successful amplifier-free 112-Gb/s transmission is performed over 2 km using low complexity three-taps equalization. We also study the tradeoff between receiver bandwidth, equalizer length and performance, and show successful signal recovery with bandwidths as low as 18 GHz when increasing the equalizer length. [ABSTRACT FROM PUBLISHER]