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We have demonstrated a semiconductor optical amplifier and electroabsorption modulator monolithically integrated with a novel dual-waveguide spot-size converter at the input for low-loss coupling to planar lightguide circuit silica waveguides or cleaved single-mode optical fiber. These devices exhibit greater than 10 dB fiber-to-fiber gain, output power of +4 dBm, 3-dB modulation bandwidth of 6 GHz, and modulator extinction ratios of 20 dB dc and 14.4 dB RF for a 2.4-V/sub pp/ drive.

We present the design, fabrication, and demonstration of a 10/spl times/10 matrix-addressed vertical-cavity top-surface-emitting laser (VCSEL) array. These arrays are batch-fabricated from full 3-in diameter GaAs/AlGaAs wafers. We show that no performance-penalty is paid using top-contacted matrix addressed pixels over conventional planar VCSEL devices. A computer-controlled display system for electrically addressing the array was designed and constructed to permit video demonstration and array testing. >

The structure, processing, and performance of arrays of integrated field-effect transistor-self-electrooptic effects devices (FET-SEEDs) consisting of doped-channel field-effect transistors, multiple quantum-well (MQW) modulators, and p-i-n MQW detectors are discussed. The performance of the FETs and SEEDs such as g/sub m/ and contrast, is equivalent to that obtained when they are made separately. Typical values are g/sub m/=80 mS/mm and contrast of 3. The largest arrays contain 128 circuits. The circuits operate at speeds as fast as 500 Mb/s, with optical input switching energy of approximately=400 fJ. At 170 Mb/s, the required optical input switching energy is approximately=70 fJ. This optical energy is at least a factor of 20 less than for symmetric SEEDs (S-SEEDs) with the same optical window sizes. Hence, FET-SEEDs provide superior performance compared to conventional S-SEEDs. >

We report on the design, fabrication and characterization of a novel 40 Gb/s optical receiver. The device consists of a high-speed waveguide photodiode monolithically integrated with a semiconductor optical amplifier to create a fully photonic receiver. We have achieved a back-to-back receiver sensitivity of -17 dBm for NRZ data transmission at 40 Gb/s. When used with an erbium doped fiber preamplifier a sensitivity of -32 dBm or 123 photons/bit has been realized for RZ transmission with -6 dBm input power at the receiver. The device has a small signal bandwidth of 39 GHz and a conversion gain of more than 800 Volts per Watt.

Wavelength selectable semiconductor lasers serve as tunable light sources in wavelength division multiplexed telecommunication systems. We report on 2.5 and 10 Gb/s electro-absorption modulated wavelength selectable laser modules based on highly reliable, closed-loop controlled, five-section InP wavelength selectable lasers.

Fabry-Perot and distributed feedback spot size converted 1.3 /spl mu/m lasers are demonstrated with competitive performance (/spl sim/10 mA threshold, >0.30 W/A slope) and narrow (16/spl times/9) far fields capable of coupling 45% of the output light into flat cleaved fiber. The Fabry-Perot device demonstrated error-floor-free transmission at 85/spl deg/C with a wide-open eye, uncooled 2.5 Gb/s operation up to 85/spl deg/C, and reliability of 105 FITS at 50/spl deg/C. The DFB devices have good DC performance with side mode suppression ratios of >40 dB. These devices will allow passive alignment and packaging without the need for intervening optics.

Wavelength-selectable lasers are key enablers for future all-optical networks. We report on fully functional 2.5 and 10 Gb/s EA-modulated wavelength-selectable laser modules based on a highly integrated InP chip that are suitable for high-reliability telecom applications.

We report measurements of excess wavelength chirp caused by high frequency electrical crosstalk between an electroabsorption modulator and the tuning section of a monolithically integrated DBR laser. The high tuning efficiency of the laser leads to stringent electrical isolation requirements.

In order to meet the increasing market needs for uncooled lasers for such applications as fiber- in-the-loop, high efficiency, high power, and highly reliable 1.3 micrometer uncooled InGaAsP/InP strained multi-quantum well Fabry-Perot lasers were fabricated with 50 mm wafer processing. Slope efficiency as high as 0.39 W/A and peak power as high as 46 mW at 85 degrees Celsius was obtained by optimizing the device structure for high temperature operation. We have also demonstrated excellent uniformity and reproducibility over 6 wafers. Reliability was also shown to be very good. More than 10,000 chips sites are available on a 50 mm wafer, and the cost is expected to be low. Because of the high performance, these lasers are expected to be used for various applications.

The complexity and size of interconnection-rich telephone switching systems require the extension of data buses over a large complement of frames. Physical designers have chosen bit serial transport over fiber to overcome the length limitations of coaxial cable from attenuation, to reduce cable volume, to provide isolation and avoid ground loops, to reduce RFI and EMI interference and coupling between channels, and to be able to make and break live connections without damaging the transmitter or receiver electronics. It has been shown that for certain interconnection applications there exists an optimum degree of parallelism (based on cost), depending on the data rate and the number of the channels.1 Prototype one-dimensional optical data links (1D-ODL’s) using linear 1 × n device arrays have been demonstrated in a number of laboratories and take advantage of the current infrastructure of fiber ribbon, splices, and connectors. Extending this concept to a second dimension by creating a two-dimensional optical data link (2D-ODL) using n×m device arrays may yield further economies of scale. We have constructed several prototype 2D-ODL’s (Table 1 ) using direct modulation of 2D arrays of vertical-cavity surface-emitting lasers (VCSEL’s)2 as shown in Fig. 1, and symmetric self-electro-optic effect device (S-SEED) modulators3 with Si P-I-N/bipolar OEIC receivers.4 The benefits and drawbacks of each technology will be briefly discussed.