A widely tunable 2.5-Gb/s modulated source using a distributed feedback (DFB) array and electroabsorption (EA) modulators is demonstrated. In order to overcome the optical bandwidth limitation of a single modulator, a 12 element array of modulators with varying bandgaps is integrated with a corresponding DFB array at different wavelengths. Selective area growth enables the bandgap of the modulators to be finely adjusted at a 10-mum pitch. A microelectromechanical system mirror selects the output of a particular EA and couples the light into fiber. Uniform high-speed modulation could be obtained in a butterfly package over a 36-nm tuning range.

We describe a 12-element distributed feedback laser array, with 10-μm pitch, covering a 36-nm tuning range, and having an integrated heater on each element. The novel heater design heats just the active laser yet requires only one additional contact for the entire array. Each individual laser element can be temperature tuned more than 3.2 nm in under 100 μs using its heater.

In this paper we describe a 12 element multi-wavelength laser diode array chip at the same 10 micron pitch with a 2.7 nm wavelength tuning per element that can span the 32 nm wide c-band, once again using laser selection for coarse tuning and temperature for fine tuning.

We demonstrate the first high speed InGaAs QW semiconductor lasers at 200°C. For p-p drive currents of 30 mA and 7.5 mA, operation at 2.5 Gb/s and 1.2 Gb/s are demonstrated, respectively.

We demonstrate direct modulation of a InGaAs flared semiconductor amplifier at 2.5 Gb/s at peak powers of 3.6 W (ave. power of 1.8 W). This is the highest single mode power from any high speed semiconductor source.

Summary form only given. Double-clad optical fibers are a robust, convenient medium for efficient optical amplification. Their compatibility with high-power semiconductor laser pump sources allows them to operate at saturated power levels of several watts, significantly higher than the level achievable with conventional diode-pumped fiber amplifiers. When coupled with a high-speed master oscillator, such an amplifier becomes an efficient high-speed, high-power optical transmitter. Such a source is of considerable interest for a high-speed space link. The transmitter consisted of a high-speed master laser diode, a high-gain fiber preamplifier, and a high-efficiency fiber power amplifier. The master oscillator was a Fabry-Perot laser diode centered at /spl lambda/=1072 nm, mounted in a high-speed, fiber-coupled package. The laser operated kink free to >50 mW and exhibited a 3-dB roll-off frequency of 11.1 GHz. Both the pre-amp and power amp were based on Yb-doped double-clad fibers pumped with /spl lambda/=915 nm fiber-coupled laser diodes. A polarization-independent optical isolator prevented feedback from the amplifier destabilizing the master oscillator. A free-space WDM module used to combine the signal and pump light into the core and cladding, respectively, of the pre-amp fiber, is shown.

Widely continuously tunable sources are key elements for many applications. This paper discusses the first integrated laser able to continuously tune its wavelength more than 1%: the micromechanical tunable vertical-cavity surface-emitting laser (VCSEL). These devices have demonstrated up 19.1 nm of continuous tuning, threshold currents as low as 460 /spl mu/A, and powers as high as 0.9 mW. In addition to these results, this paper discusses the tuning speed, lifetime, and applicability as a new broad-band source of these devices. Despite mechanical tuning, speeds of /spl mu/s are possible and long lifetime is expected. A detailed consideration of the design and fabrication of these devices is performed. Finally, an interesting mode switching effect is presented.

We demonstrate a surface-normal GaAs Fabry-Perot filter with 70 nm continuous tuning range requiring 5V tuning voltage. Micromechanical tuning is achieved by electrostatically deflecting the top mirror of the resonator which is freely suspended as a cantilever.

Micromechanical tunable VCSELs with dramatically improved performance are demonstrated using AlAs oxidation. Larger aperture (similar to 10 mu m) devices achieve record tuning of 19.1nm with 3.3mA threshold currents. Smaller aperture (similar to 5 mu m) devices achieve record threshold currents of 460 mu A, and output powers of 0.9mW with 7nm of tuning.

We demonstrate a resonant cavity wavelength tunable detector with a record 30-nm continuous tuning range, 17-dB extinction ratio, and a low 7-V tuning voltage. The detector map be biased to operate in one of two modes. In the first, the detector is tuned to a specific wavelength. In the second, the detector can be tuned to a nominal wavelength and remain locked to the wavelength of the incident light despite wavelength variations. Consequently, this detector is ideal for operation as a cost-effective and robust receiver for WDM communication systems, spectroscopic applications, and wavelength measurement.