Vertical-cavity Surface-emitting Laser Module Research Articles

Optical modulation waves excited in microlaser arrays

Long-range coherence in periodically arranged microlaser arrays is analyzed, employing vertical-cavity surface-emitting lasers (VCSELs) as a case study. It is shown that periodic VCSEL arrays behave as oscillator lattices coupled through near-neighbor interactions. Modulation of an individual VCSEL excites intensity waves through the array. The dispersion relation for the lattice waves, the excited bandwidth, and the modulation decay length are obtained as functions of the individual cavity parameters and lattice constants. For practical applications, the correlation length limits in the array packing density for a given tolerance to VCSEL cross talk.

Data transparent reconfigurable optical interconnections using polarization switching in VCSEL's induced by optical injection

We demonstrate a data transparent reconfigurable optical interconnection system based on optical injection controlled polarization switching in a master-slave vertical-cavity surface-emitting laser (VCSEL) configuration. A 140-Mb/s data stream generated by the slave VCSEL is redirected by an anisotropic diffractive optical element depending on the polarization state of the emitted light. The polarization of the slave laser is controlled by injecting an orthogonally polarized optical signal from a master laser. The current modulation of the master VCSEL and the subsequent polarization switching of the slave VCSEL occur at 40 MHz. In our setup, both the data rate and the optical interconnection reconfiguration rate are limited by the electronic drive circuitry and could in principle attain the gigahertz range.

Smart integration and packaging of 2D VCSEL's for high-speed parallel links

This paper reviews recent progress in the integration and packaging of two-dimensional (2D) vertical-cavity surface-emitting laser (VCSEL) arrays being developed for the use in high-speed parallel optical interconnections. It reviews the smart integration of VCSEL's with detecting, switching and latching functions through the integration of a VCSEL-thyristor and double-cavity phototransistor. It also describes self-alignment-packaging technologies for 2D VCSEL module that can be used in high-density parallel links. Various system applications, such as a distributed fiber switch used to enable crossbar interconnections with address switching functions and hyper-parallel transmission using an image fiber, are also examined.

A 16 x 16 optical full-cross-bar connection module with VCSEL-array push/pull module and polymer-waveguide coupler connector

A 16-ch/spl times/16-ch optical full-cross-bar connection module is demonstrated by fabricating an optical cross connector to configure a cross-bar connection, a 16-ch two-dimensional push/pull receptacle-type vertical-cavity surface-emitting laser (VCSEL) array module, and a 16/spl times/1 ch plug-type coresize-conversion polymer-waveguide coupler connector. This configuration makes an all-optical space-division switch possible using simple, compact and low-cost components. The fabricated VCSEL module exhibits an insertion loss of 2.1/spl plusmn/0.8 dB, and the coupler connector with the cross connector exhibits an insertion loss of 4.6/spl plusmn/0.3 dB. The resulting total loss of 6.7/spl plusmn/1.1 dB from VCSEL to fiber output after the cross-bar connection is sufficiently low to apply for an optical network switch.

Thermal management of VCSEL-based optoelectronic modules

Thermal management is critical to reliable optoelectronic modules based on vertical-cavity surface-emitting lasers (VCSELs). One critical thermal path to be managed is from a VCSEL to a case (heat sink), which is affected by packaging technologies and materials The measured VCSEL-to-case resistance of a laser with 8-/spl mu/m aperture was 1650/spl deg/C/W, and that of a 20-/spl mu/m device was 1070/spl deg/C/W. These thermal resistances are much larger than those for the edge-emitting lasers; advanced device and packaging technologies are being developed to reduce these resistances. To study the packaging effects, a three-dimensional (3-D) numerical model has been developed and calibrated by the measured data. The calibrated model was used to understand the difference in thermal behavior: 1) between a wire-bonded and a flip-chip VCSEL module, 2) between a single-VCSEL and an 8/spl times/8 VCSEL module, and 3) between a bottom-cooled and a top-cooled module.

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 xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>