Frequently quoted advantages of VCSELs over other optical sources include wafer scale fabrication and testing, low
cost, ease of fabricating arrays and ease of fiber coupling. To benefit from these advantages a robust manufacturing
process and product demand are needed. Avago Technologies produces a range of single channel and parallel optical
link products incorporating 850nm band VCSEL sources operating at up to 10Gb/s per channel. This paper will explore
some important factors which need to be controlled for manufacturability of VCSEL devices.
Laser-based projection displays have long attracted interest because of the multiple advantages (expanded color gamut, high resolution, longer lifetime, etc.) expected from lasers as compared to lamps. However, most of these advantages have been largely negated by the significant cost, size, and cooling requirements associated with lasers, and their inability to produce red, green, and blue colors in the same platform. In this paper, we review a new, laser array
technology based of frequency-doubled, semiconductor, surface-emitting lasers. The key features of this technology, such as demonstrated multi-Watt output for rear-projection TVs, power levels scalable with the number of emitters, speckle suppression due to multi-emitter array, and a low-cost and compact design are discussed in detail.
In this paper, we will present the recent progress of electrically-pumped directly-modulated tunable 1550 nm VCSEL development at Bandwidth9. The device is fabricated from an all epitaxial VCSEL structure grown on an InP substrate, with a monolithically integrated tuning arm for continuous wavelength tuning. We have demonstrated over 1 mW CW output power and over 20 nm tuning range in C-band and error free transmission performance at 2.5 Gbps over 100 km SMF-28 fiber. The reliability test data of the tunable VCSELs shows a projected failure rate of less than 400 FITS.
Use of aluminum-free epitaxial structures for near-infrared laser diodes has been an active research area in the past decade. These edge-emitting laser diodes have demonstrated operational lifetimes exceeding 10,000 hours at high output powers and high efficiencies. Improvements in epitaxial structure, processing, and packaging have enabled these results. In this paper, we will review developments in aluminum-free laser diodes. We describe our recent work with these devices and conclude by discussing reliability issues.
This paper presents the performance characteristics and reliability data of AlGaInP-based VISIBLE laser diodes emitting at the wavelengths from 630 to 670 nm. The lasers are grown by toxic gas free solid source molecular beam epitaxy.
Temperature dependent efficiency and modulation characteristics of strained quantum well (QW) InGaAs/InGaAsP/InGaP 980 nm laser diodes of various designs are analyzed using self consistent carrier transport analysis including stimulated emission. The decrease of the differential efficiency of 980 nm laser diodes with temperature is found to be caused by an increased modal loss attributed to the free carrier (electron and hole) absorption. The obtained results agree well with experimentally observed increase of internal loss at higher temperatures. Modulation characteristics are determined mainly by drift-diffusion in separate confinement region along with processes of carrier capture and escape in QWs. At high temperatures modulation bandwidth is reduced because of the decrease in differential gain. Graded index separate confinement heterostructure and multi-QW lasers show superior efficiency and modulation behavior at high temperatures.
Semiconductor master oscillator power amplifier (MOPA) devices based on the resonant transmission properties of resonant-optical-waveguide (ROW) antiguided structures are shown to be promising candidates for stable, coherent, high-power sources. A novel mast oscillator for this type of MOPA is proposed: the three-core antiresonant reflecting optical waveguide (ARROW) diode laser. This device is also based on ROW antiguided structures and can easily be integrated with the power amplifier. Three-core ARROW lasers are shown to have large intermodal discrimination against unwanted modes, and when used as the maser oscillator of a ROW-MOPA, a uniform near-field, flat-phasefront, diffraction-limited beam output is obtained. Experimentally, 350 mW diffraction-limited beam operation has been demonstrated in ROW-MOPA devices without extremely low AR coatings.
The effect of gain spatial hole burning on antiguided arrays is analyzed for the first time. Nonresonant devices, due to the nonuniformity of the in-phase-mode intensity profile, experience self-focusing and multimode operation with increasing drive level similar to the behavior of evanescent-wave-coupled devices. Resonant and near-resonant devices (i.e. resonant-optical-waveguide (ROW) arrays), due to the uniformity of the in-phase mode, display some mild defocusing with increasing drive level, while the nearest high-order mode cannot reach threshold up to drive levels in excess of 10X threshold. These results explain the fundamental single-mode stability of ROW arrays, in excellent agreement with experimental data.