C. A. Burrus

Broadly tunable InGaAsP/InP laser based on a vertical coupler filter with 57‐nm tuning range

We have integrated a broadly tunable grating‐assisted vertical coupler as an intracavity filter to demonstrate a novel monolithic multiple‐quantum‐well InGaAsP/InP laser. The narrow, bandpass intracavity filter results in an extended cavity laser with a measured electrical tuning range of 57 nm with single‐frequency operation over most of that range.

High-speed modulation of vertical-cavity surface-emitting lasers

The IM (intensity modulation) and FM (frequency modulation) characteristics of vertical-cavity surface-emitting lasers are studied. The laser has high FM efficiency and broad IM bandwidth (near 8 GHz) at a very low bias (4.5 mA). Five Gb/s pseudorandom direct intensity modulation of this laser with open eyes is demonstrated.<<ETX>>

Broadly Tunable InGaAsP/Inp Buried Rib Waveguide Vertical Coupler Filter

We report the first demonstration of broadly electrically tunable (215 A), narrow‐band (∼20 A full width at half maximum), wavelength selective, grating‐assisted coupling between vertically stacked buried rib InGaAsP/InP channel waveguides. This current injection tuned device is suitable for integration in a variety of photonic devices and integrated circuits including broadly tunable extended cavity lasers, amplifier/filter, and demultiplexer/detector circuits.

Broadly tunable vertical‐coupler filtered tensile‐strained InGaAs/InGaAsP multiple quantum well laser

Using tensile‐strained InGaAs/InGaAsP multiple quantum well material to increase the gain bandwidth, we demonstrate a tuning range of 74.4 nm with sidemode‐suppression ratio of ≳25 dB and as high as 34 dB in a broadly tunable vertical‐coupler filtered laser at 1.55 μm. Due to its wide gain bandwidth and significant gain‐peak shift to shorter wavelengths with gain current increase, the tensile‐strained quantum well material is well suited for broadly tunable lasers.

Monolithic integrated InGaAsP/InP distributed feedback laser with Y‐branching waveguide and a monitoring photodetector grown by metalorganic chemical vapor deposition

We have fabricated an integrated 1.5 μm distributed feedback laser (DFB) with a Y‐branching waveguide and a monitoring photodetector, grown entirely by metalorganic chemical vapor deposition. The integrated device is designed to resolve the frontface‐backface mistracking problem of the DFB laser and to demonstrate monolithic integration of fundamental building blocks for photonic integrated circuits.

Balanced operation of a GaInAs/GaInAsP multiple-quantum-well integrated heterodyne receiver

The balanced operation of a multiple-quantum-well balanced heterodyne receiver photonic integrated circuit (PIC) is described. Using only SMA-connected 50 Omega commercial electronics, a free-space beam sensitivity of -42.3 dBm at 108 Mb/s and -39.7 dBm at 200 Mb/s for NRZ FSK (frequency-shift keying) reception has been achieved. This represents a 14 dB improvement over any previous heterodyne receiver PIC sensitivity. In addition to providing the multichannel benefits of heterodyne reception, this is also the highest sensitivity yet reported for any OEIC (optoelectronic integrated circuit) receiver. >

InGaAs/InGaAsP integrated tunable detector grown by chemical beam epitaxy

By controlling the thickness of the grating depth with chemical beam epitaxy (CBE) growth time, we report in this letter the design and performance of an integrated tunable detector. A carefully designed tunable active filter, which allows only one below threshold Fabry–Perot mode for operation, is integrated with a waveguide detector. The full tuning range of this kind of tunable device can now be utilized for system applications.

Continuous tunability in three‐terminal coupled‐cavity lasers

The continuous tunability of various coupled‐cavity semiconductor lasers has been investigated. Monolithic etched groove and cleaved coupled cavity (C3) geometries are included. Using a special method of modulating the laser currents, appreciable tuning ranges have been achieved (∼8 A) without mode hops. Also, electronic tuning of a laser with no amplitude variation is illustrated. A tuning range of 4 A with <5% AM depth is observed. Review of the theory and a comparison of the different laser geometries are included.

Integration of 1.3 μm wavelength lasers and optical amplifiers

We describe integration of lasers and optical amplifiers at 1.3 μm wavelength. The effects of the residual mirror reflectivity at the amplifier front facet are discussed. Using photonic integration techniques very high coupling efficiency of light from the laser to the amplifier sections was observed, with current transfer efficiency (ratio of photocurrent to drive current) as high as 33%. The output light current characteristics of the laser have a slope efficiency higher than 2 mW/mA. This device may be used for digital modulation with very low rf power drive requirements. Modulation at 2 Gbit/s has been demonstrated.

Electro-optical logic operations with two-electrode distributed feedback injection lasers

A complete set of and, or, nand, nor, and invert logic gates is demonstrated using a distributed feedback (DFB) injection laser with two‐electrode current control. The logic operation is based on the high‐speed two‐wavelength switching using the two‐mode degeneracy property of DFB lasers that we have demonstrated recently. A 400‐ps switching time, limited by the speed of the electrical signal, was observed. The device is compatible with future photonic integrated circuit and wide‐band optical fiber transmission technologies.