20060731-214946 VCSEL Transceivers
For tunable transceiver based networks, to reduce packet delay, fast tunable transceiver should be considered.   In terms of technology, fast-tunable transceivers are generally a less mature technology than fixed-tuned transceiver arrays. More specifically fast-tunable transmitters have been proven to be feasible in a cost-effective manner [shri01], while fast tunable optical filter receivers with acceptable channel crosstalk remain a technical challenge at the photonics level [fan05].   Compared from cost-effectiveness, presently fast-tunable transceivers are much more costly than their fixed tuned counterparts [berr04]. Nowadays, tunable laser are mainly used in WAN. Tunable lasers aren’t yet meant to compete with the lower-cost (i.e., fixed) lasers used in either MAN or LAN nowadays [full05].   The discussed network is a star network with passive star coupler in the central and network nodes are equipped with fixed transceiver arrays. In such configuration, the cost of fixed transceiver arrays may dominate other components.   For a star network used in access, and fixed transceiver array are intended to function as components in systems such as data links, which transmit information in the form of light within optical fibers. For a system such as a data link to be cost-effective, its price cannot exceed, say, $100. So a single, if indispensable component the fixed transceiver array can cost no more than about $10. The way to achieve that comparatively low cost is through mass production.   With the rapid advance of optical component technology, VCSEL (Vertical Cavity Surface Emitting Laser) based fixed transceiver array chips have been commercially available. One of the key features of VCSELs is their structure can be integrated in one or two-dimensional array configuration, [lasermate, emcore, kris00].   To achieve the goal of mass production and be cost-effective, VCSEL research basically asks the question how tens of thousands of little lasers can be made inexpensively and reliably on a semiconductor wafer [ucsb].   The wavelength of commercially available VCSELs can be divided into short wavelength (mainly 850nm) [mich03] or long wavelength (λ≥1.3µm) [compsemi, orts06].   Long wavelength VCSELs are mainly used in long-haul transmission, and less mature than short wavelength VCSELs [orts06].   Two important enabling technologies for long wavelength VCSEL mass production are Molecular Beam Epitaxy (MBE) [reddy02, cold02] and Buried Tunnel Junction (BTJ) [vbtj, shau04]. With respect to the anticipated high-volume markets for VCSEL applications, cost-effective production is mandatory. The BTJ concept offers the advantage of full-wafer manufacturability even for larger diameters than the commonly used 2-inch size [orts06].   1550nm ranged commercial VCSEL transceiver modules can be found from OPNEXT \em{opnext]. For 1550nm ranged VCSEL transmitter chip/die/array, commercial suppliers include [raycan, beamx, vertilas].   With the advance of long wavelength VCSEL research and increased commercial deployment, for long-haul transmission, one can expect long wavelength VCSEL transceiver array to be more cost-effective in the near future owing to economies of scale.     Commercial available short wavelength VCSELs can be found in [lasermate, aoc]. They are so superior to traditional edge-emitting lasers that they have completely replaced them in distances less than 300 meters [lars02], and already dominate the market in short-reach links, those less than 2 km [mats02].   Till 2003, Short wavelength VCSELs have found a variety of applications and nowadays cover more than 70% of all the market of semiconductor lasers. This is due to the favorable concurrence in these lasers of good characteristics and low costs [debe03].      Reference   [ucsb] UCSB Press, `` Research Breakthrough for Fiber Optic Communications -- Single-Crystal Semiconductor Lasers Grown in One Step Will Function as Low-Cost Transmitters,'' http://www.engineering.ucsb.edu/Announce/vcsel.html   [reddy02] M.H.M. Reddy, A. Huntington, D. Buell, R. Koda, E. Hall, and L.A. Coldren, ``Molecular Beam Epitaxy Growth of High-Quality Active Regions with Strained In(x)Ga(1-x) As Quantum Wells and Lattice-Matched Al(x)Ga(y)In(1-xy) As Barriers Using Sub-Monolayer Superlattices,'' [ Application Physics Letters, ] pp. 3509-3511, May 2002.   [cold02] L. Coldren, ``Monolithic InP-Based Long-Wavelength VCSELs,'' Project Report 2001-02 for MICRO Project 01-018, Department of Electrical and Computer Engineering University of California, Santa Barbara, and Honeywell Technology Center.   [vbtj] Vertilas GmbH, ``The VERTILAS Breakthrough: Buried Tunnel Junction (BTJ) VCSEL,'' http://www.vertilas.com/technologie_innovation.php   [shau04] R. Shau, M. Ortsiefer, J. Rosskopf, G. Bohm, C. Lauer, M. Maute, and M. C. Amann, ``Long-Wavelength InP-based VCSELs with Buried Tunnel Junction: Properties and Applications,'' [ Proceedings of Vertical-Cavity Surface-Emitting Lasers VIII, SPIE,] pp. 1–15, 2004.   [orts06] M. Ortsiefer, ``Fabricating Buried Tunnel Junctions for InP-based VCSELs,'' [ Solid State Technology, ] http://sst.pennnet.com/Articles/Article_Display.cfm?ARTICLE_ID=247491, Feb, 2006   [debe03] P. Debernardi, G. P. Bava, F. Monti, M. B. Willemsen, ``Features of Vectorial Modes in Phase-Coupled VCSEL Arrays: Experiments and Theory,'' {\em Journal of IEEE Quantum Electronics,] vol. 39, no. 1, pp. 109-119, Jan. 2003.   [shri01] K. V. Shrikhande, I. M. White, M. Rogge, F.-T. An, A. Srivatsa, E. Hu, S.-H. Yam, and L. Kazovsky, ``Performance Demonstration of a Fast–Tunable Transmitter and Burst–Mode Packet Receiver for HORNET,'' [ Proceedings of OFC,] vol. 4, pp. ThG–1–ThG–3, 2001.   [fan05] C. Fan, S. Adams, and M. Reisslein, ``The $FT^{\Lambda]-FR^{\Lambda]$ AWG Network: A Practical and Efficient Single-Hop Metro WDM Network for Uni- and Multicasting,'' IEEE/OSA Journal of Lightwave Technology, vol. 23, no. 3, pp. 937-954, 2005.   [berr04] R. Berry and E. Modiano, ``Using Tunable Optical Transceivers for Reducing the Number of Ports in WDM/TDM Networks,'' [ IEEE/OSA Optical Fiber Conference (OFC),] vol. 1, Feb. 2004.   [full05] M. Fuller ``SFPs Challenging Tunable Lasers in Metro,'' [ Lightwave, ] http://lw.pennnet.com/Articles/Article_Display.cfm?Section=ARTCL&ARTICLE_ID=229361&VERSION_NUM=2&p=13, Jun. 2005.   [raycan] RayCan, ``1550nm Single Mode VCSEL Chip, Die, Array,'' http://www.raycan.com/raycan_product.htm [beamx] Beam eXpress, ``Long Wavelength VCSEL,'' http://www.beamexpress.com/vcsel.php [vertilas] Vertilas GmbH, ``VCSEL Laser Diodes for Optical Communications -- VL-1550 Series,'' http://www.vertilas.com/pdf/Telecom_rev20.pdf [opnext] Opnext, ``10 GbE XENPAK Modules and DWDM XENPAK Modules,'' http://www.opnext.com/products/details/XENPAK_DWDM.cfm, http://www.opnext.com/products/details/XENPAK.cfm   [lars02] E. Larson, and P. Rigby, ``Siros Gets $17 Million in Funding,'' [ Light Reading, ] http://www.lightreading.com/document.asp?doc_id=12456, Mar. 2002.   [mich03] R. Michalzik, H. Roscher, M. Stach, D. Wiedenmann, M. Miller, J. Broeng, A. Petersson, N. A. Mortensen, H. R. Simonsen, and E. Kube, ``Recent progress in short-wavelength VCSEL-based optical interconnections,'' [ Semiconductor Optoelectronic Devices for Lightwave Communication,] SPIE vol 5248, pp. 117-126, Dec. 2003.   [lasermate] Lasermate Group, `` Brief in VCSEL,'' http://www.lasermate.com/vcsel.htm   [compsemi] CompundSemicoductor.net ``Commercializing Long-Wavelength VCSELs (Cover Story - VCSELs),'' [ IOP, ] http://www.compoundsemiconductor.net/articles/magazine/7/6/65/1, Jun. 2001   [mats02] C. Matsumoto, ``VCSELs Can Bring Optics to the Masses,'' [ EE Times, ] http://www.eet.com/reshaping/optical/OEG20020911S0060, Sep. 2002.   [aoc] Advanced Optical Components, ``850nm VCSELs & Detectors – Datacom,'' http://www.advancedopticalcomponents.com/product/datacom.php   [emcore] Emcore, ``Product Brief – 1 x 12 VCSEL Array 2.7-3.6Gb/s,'' http://www.emcore.com/assets/fiber/pb.1X12_VCSEL_array.2004-9-15.EMCORE.pdf   [kris00] A. V. Krishnamoorthy, K. W. Goossen, L. M. F. Chirovsky, R. G. Rozier, P.   Chandramani, S. P. Hui, J. Lopata, J. A. Walker, amd L. A. D'Asaro, ``16×16 VCSEL Array Flip-Chip Bonded to CMOS VLSI Circuit,'' [ IEEE Photonics Technology Letters, ] vol.12 no 8, Aug. 2000.

<  top   | back   | topic index  >