100-Gb/s dense wavelength division multiplexed (DWDM) transmitter and receiver photonic integrated circuits (PICs) are demonstrated. The transmitter is realized through the integration of over 50 discrete functions onto a single monolithic InP chip. The resultant DWDM PICs are capable of simultaneously transmitting and receiving ten wavelengths at 10 Gb/s on a DWDM wavelength grid. Optical system performance results across a representative DWDM long-haul link are presented for a next-generation optical transport system using these large-scale PICs. The large-scale PIC enables significant reductions in cost, packaging complexity, size, fiber coupling, and power consumption.

The temperature dependence and power output of vertical-cavity surface-emitting lasers (VCSELs) are addressed. The peak wavelength of the quantum well has been offset from the wavelength of the device cavity mode so that they are aligned at elevated temperatures. The result of this design change is to produce an 8- mu m-diameter VCSEL capable of operation to 145 degrees C, as well as CW operation of broad-area (70- mu m diameter) heat-sunk devices to record power levels. Fiber coupling experiments were also carried out, and a record 33-mW CW power was coupled to a multimode fiber.<>

We report on a technique of grading the heterobarrier interfaces of a p‐type distributed Bragg reflector mirror to reduce the operating voltages of vertical‐cavity surface‐emitting lasers (VCSELs). We report VCSELs with lower operating voltages (2–3 V) and record continuous‐wave room‐temperature power‐conversion efficiencies (17.3%). We experimentally demonstrate that by using a parabolic grading and modulating the doping correctly, a flat valence band is generated that provides low voltage hole transport. The low resistance mirrors are achieved using low Be doping, digital‐alloy grading and 600 °C growth temperatures.

The authors describe the first 1300 nm VCSELs which are compatible with commercial datacom performance requirements. These devices operate at CW up to 80°C. The threshold current varies by only ± 0.5 mA (± 10%) from 0 to 70°C. The devices show > 0.38 mW singlemode output and < 2.8 V operating from 0 to 70°C. The same devices also demonstrate a 1.25 Gbit/s modulation speed.

Contacts have been made to p- and n-type layers on opposite sides of the active region within the cavity of an InGaAs vertical cavity surface emitting laser. The two concentric ring contacts allow all electrical connections on and emission from the top surface of a semi-insulating GaAs substrate. The design includes a novel current leveling layer to minimize current crowding effects. A high external quantum efficiency of 46% has been measured with maximum output powers up to 6 mW for a 15 /spl mu/m diameter device and threshold currents of 0.72 mA for a 7 /spl mu/m diameter laser.

We describe and characterize a multi-micron silicon photonics platform which has been designed to combine performance, power efficiency, manufacturability and versatility for integrated photonic applications ranging from data communications to sensors. We outline the attributes needed for broad applicability, high-volume manufacturing, and large-scale deployment of silicon photonics, and describe how the platform is favorable with respect to these attributes. We present demonstrations of key technologies needed for the communications and sensing applications, including low-loss fiber attach, compact low-loss filters, efficient hybrid wavelength division multiplexed lasers, and high speed electro-absorption modulators and integrated photodetectors.