G. Suruceanu

1.5-mW single-mode operation of wafer-fused 1550-nm VCSELs

We demonstrate 1.5-/spl mu/m waveband wafer-fused InGaAlAs-InP-AlGaAs-GaAs vertical-cavity surface-emitting lasers (VCSELs) emitting high single-mode power of 1.5 mW at room temperature with sidemode suppression ratio of over 30 dB and a full-width at half-maximum far field angle of 9/spl deg/. These devices have thermal resistance value below 1.5 K/mW and are emitting 0.2 mW at 70/spl deg/C. VCSELs with a wavelength span of 40-nm emission are produced from the same active cavity material, which shows the potential of realizing multiple-wavelength VCSEL arrays.

High-performance single-mode VCSELs in the 1310-nm waveband

High-performance vertical-cavity surface-emitting lasers (VCSELs) emitting in the 1310-nm waveband are fabricated by bonding AlGaAs-GaAs distributed Bragg reflectors on both sides of a InP-based cavity. A 2-in wafer bonding process is optimized to produce very good on-wafer device parameter uniformity. Carrier injection is implemented via double intracavity contact layers and a tunnel junction. A 1.2-mW single-mode output power is obtained in the temperature range of 20/spl deg/C-80/spl deg/C. Modulation capability at 3.2 Gb/s is demonstrated up to 70/spl deg/C. Overall VCSEL performance complies with the requirements of the 10 GBASE-LX4 IEEE.802.3ae standard, which opens the way for novel applications of VCSELs emitting in the 1310-nm band.

Cavity Mode—Gain Peak Tradeoff for 1320-nm Wafer-Fused VCSELs With 3-mW Single-Mode Emission Power and 10-Gb/s Modulation Speed Up to 70

Room-temperature cavity mode red-shift of about 45nm from the photoluminescence peak is found to be optimal for tradeoff between high modulation bandwidth and good high-temperature performance for InAlGaAs(InP)-AlGaAs fused vertical-cavity surface-emitting lasers (VCSELs) employing tunnel junction carrier injection. Single-mode output power up to 5.4 and 3.1 mW, at 25 degC and 75 degC, respectively, and open eye diagrams exhibiting fall time values close to 40 ps at 10-Gb/s modulation up to at least 70 degC have been obtained for such VCSELs emitting at 1320-nm wavelength

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The development of the 10GBASE-LX4 communication standard for aggregated 10-Gb/s rates feeds the need for low-cost laser sources in the 1275-1350-nm wavelength range operating at modulation rates of 3.125 Gb/s. We present comprehensive characterization of wafer fused vertical-cavity surface-emitting lasers with characteristics that meet the IEEE802.3ae specification for 10GBASE-LX4. These include output power greater than 1.5 mW up to 80degC, wavelength around 1340 nm, single-mode emission and modulation at 3.125 Gb/s, and wide open eyes with rise and fall times below 100 ps up to 70degC

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Wafer fusion vertical cavity surface emitting laser (VCSEL) technology has produced devices that successfully passed all mechanical and electrical Telcordia qualification tests. Accelerated lifetime tests result in times to 1% failure at 70<formula formulatype=inline><tex Notation=TeX>

3.125-Gb/s modulation up to 70/spl deg/C using 1.3-/spl mu/m VCSELs fabricated with localized wafer fusion for 10GBASE LX4 applications

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Reliability of 1310 nm Wafer Fused VCSELs

</tex></formula> of 18 years and 30 years at VCSEL driving currents of 9 and 8 mA, respectively. These lifetimes meet the telecom industry reliability requirements for applications in fiber-optic communications networks.

Recent developments in long wavelength VCSELs based on localized wafer fusion

We review recent results on wafer fused long wavelength VCSELs emitting in the 1310 – 2000 nm range. This technology allows reaching fundamental mode output in excess of 4.5 mW at room temperature and close to 3 mW at 70 °C for both the 1310 nm and 1550 nm wavebands-the highest values obtained so far. Emission wavelength can be tuned continuously with current with a tuning range as large as 15 nm. For 2000 nm emission wavelength, room temperature output is ∼ 0.5 mW, limited so far by high optical absorption in the cavity. 1310 nm-VCSELs that are optimized for high speed operation yield excellent 10 Gbps operation both at room temperature and at 100 °C.

Increasing single mode power of 13-μm VCSELs by output coupling optimization

We report on the single mode emission power enhancement of 1.3-μm VCSELs by adjusting the reflectivity of the top GaAs-based DBR for output coupling optimization using selective removal of Bragg reflector layers. Devices with record single mode power of 6.8-mW at room temperature and 2.8-mW at 80°C, with more than 30 dB single mode suppression ratio, have been obtained.

VCSEL-based processing of microwave signals

Several demonstrations of new concepts of microwave photonics devices based on cost- and power effective long-wavelength vertical cavity surface emitting lasers (LW-VCSELs)are presented and discussed.