Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Single-mode 1.27 μm InGaAs vertical cavity surface-emitting lasers with temperature-tolerant modulation characteristics
KTH, School of Information and Communication Technology (ICT), Microelectronics and Applied Physics, MAP.
KTH, School of Information and Communication Technology (ICT), Optics and Photonics.ORCID iD: 0000-0003-3056-4678
KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
KTH, School of Information and Communication Technology (ICT), Integrated Devices and Circuits.ORCID iD: 0000-0002-9040-4740
Show others and affiliations
2005 (English)In: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 86, no 21, 211109-1-211109-3 p.Article in journal (Refereed) Published
Abstract [en]

The dynamic performance of InGaAs/GaAs 1.27 μ m single-mode vertical cavity surface emitting lasers (VCSELs) is presented. In order to reach such a long wavelength, the devices utilize highly strained double-quantum wells and a large detuning between the material gain peak and cavity resonance. It is found that the large detuning improves the temperature stability of both static and modulation characteristics. A resonance frequency of 7.8-9.5 GHz and optical power of 0.30 mW in fiber was maintained throughout the investigated temperature range of 20-90 ° C. The intrinsic response of the device suggests that long-wavelength InGaAs/GaAs VCSELs have the potential to be used as low cost uncooled optical transmitters at 10 Gbit/s. © 2005 American Institute of Physics. © 2005 American Institute of Physics.

Place, publisher, year, edition, pages
2005. Vol. 86, no 21, 211109-1-211109-3 p.
Keyword [en]
Dispersion (waves); Modulation; Resonance; Semiconducting indium gallium arsenide; Semiconductor quantum wells; Thermodynamic stability; Optical transmitters; Resonance frequency; Surface emitting lasers; Temperature tolerant modulation characteristics
National Category
Atom and Molecular Physics and Optics
Identifiers
URN: urn:nbn:se:kth:diva-8623DOI: 10.1063/1.1935755ISI: 000229544200009Scopus ID: 2-s2.0-20844447649OAI: oai:DiVA.org:kth-8623DiVA: diva2:13995
Note
QC 20100707Available from: 2008-06-03 Created: 2008-06-03 Last updated: 2017-12-14Bibliographically approved
In thesis
1. Design and fabrication of long wavelength vertical cavity lasers on GaAs substrates
Open this publication in new window or tab >>Design and fabrication of long wavelength vertical cavity lasers on GaAs substrates
2008 (English)Doctoral thesis, comprehensive summary (Other scientific)
Abstract [en]

Vertical cavity surface emitting lasers (VCSELs) are today a commodity on the short wavelength laser market due to the ease with which they are manufactured. Much effort has in the last decade been directed towards making long wavelength VCSELs as successful in the marketplace. This has not been achieved due to the much more difficult fabrication technologies needed for realising high performance long wavelength VCSELs. At one point, GaInNAs quantum wells gain regions grown on GaAs substrates seemed to be the solution as it enabled all-epitaxial VCSELs that could make use of high contrast AlGaAs-based distributed Bragg reflectors (DBRs) as mirrors and lateral selective oxidation for optical and electrical confinement, thereby mimicking the successful design of short wavelength VCSELs. Although very good device results were achieved, reproducible and reliable epitaxial growth of GaInNAs quantum wells proved difficult and the technology has not made its way into high-volume production. Other approaches to the manufacturing and material problems have been to combine mature InP-based gain regions with high contrast AlGaAs-based DBRs by wafer fusion or with high contrast dielectric DBRs. Commonly, a patterned tunnel junction provides the electrical confinement in these VCSELs. Excellent performance has been achieved in this way but the fabrication process is difficult.

In this work, we have employed high strain InGaAs quantum wells along with large detuning between the gain peak and the emission wavelength to realize GaAs-based long wavelength VCSELs. All-epitaxial VCSELs with AlGaAs-based DBRs and lateral oxidation confinement were fabricated and evaluated. The efficiency of these VCSELs was limited due to the optical absorption in the doped DBRs. To improve the efficiency and manufacturability, two novel optical and electrical confinement schemes based on epitaxial regrowth of current blocking layers were developed. The first scheme is based on a single regrowth step and requires very precise processing. This scheme was therefore not developed beyond the first generation but single mode power of 0.3 mW at low temperature, -10ºC, was achieved. The second scheme is based on two epitaxial regrowth steps and does not require as precise processing. Several generations of this design were manufactured and resulted in record high power of 8 mW at low temperature, 5ºC, and more than 3 mW at high temperature, 85ºC. Single mode power was more modest with 1.5 mW at low temperature and 0.8 mW at high temperature, comparable to the performance of the single mode lateral oxidation confined VCSELs. The reason for the modest single mode power was found to be a non-optimal cavity shape after the second regrowth that leads to poor lateral overlap between the gain in the quantum wells and the intensity of the optical field.

Place, publisher, year, edition, pages
Stockholm: KTH, 2008. 79 p.
Series
Trita-ICT/MAP AVH, ISSN 1653-7610 ; 2008:10
Keyword
VCSEL, Selective Area Epitaxy, Epitaxial regrowth, Laser
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:kth:diva-4795 (URN)978-91-7178-990-7 (ISBN)
Public defence
2008-06-12, N2, Electrum 3, Isafjordsgatan 28 A/D, Kista, 10:00
Opponent
Supervisors
Note
QC 20100825Available from: 2008-06-03 Created: 2008-06-03 Last updated: 2010-08-25Bibliographically approved
2. Dynamic Characterization of Semiconductor Lasers and Intensity Modulators
Open this publication in new window or tab >>Dynamic Characterization of Semiconductor Lasers and Intensity Modulators
2009 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The research work presented in this thesis deals with characterization ofdynamics of active photonic devices that are based on semiconductormaterials. The thesis contains an introduction and a collection of publishedarticles in peer reviewed international journals and conferences.The introduction starts with the physical background and a review of thesemiconductor material properties which both affects the design andfabrication of the devices and determine their performance in applicationssuch as wavelength, optical power and attenuation, drive current andvoltage, temperature sensitivity and modulation bandwidth.The next chapter of the introduction is dedicated to various kinds ofsemiconductor lasers. It describes the physical principles, steady stateoperation and the dynamical response. The laser is essentially an opticalcavity consisting of a material with optical gain inbetween two reflectivemirrors. Special attention is given to the spectral shape of the mirrorreflectivity and its effect on the laser dynamics and how these effects canbe distinguished from those of the gain material.In order to improve dynamic performance, it is common that the laser,instead of being directly modulated by varying the drive current, isconnected to a separate modulator. The next chapter is therefore devotedto electroabsorption modulators for high speed intensity modulation andtheir integration to lasers. In order to fully take advantage of the highintrinsic modulation bandwidth of these devices it is important to havea good microwave design to avoid electrical parasitics. A segmented paddesign to achieve this is briefly described.The last part of the introduction covers measurements techniques that wereimplemented to experimentally investigate above devices. A description ofthe measurement methods, including practical hints and methods forevaluation of the measured results are provided.

Place, publisher, year, edition, pages
Stockholm: KTH, 2009. xii, 72 p.
Series
Trita-ICT/MAP AVH, ISSN 1653-7610 ; 2009:8
National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:kth:diva-11149 (URN)
Public defence
2009-09-30, KTH-Electrum, sal/ hall C2, Isafjordsgatan 26, Kista, 10:00 (English)
Opponent
Supervisors
Note
QC 20100707Available from: 2009-09-22 Created: 2009-09-22 Last updated: 2010-07-21Bibliographically approved
3. Development of 1.3-μm GaAs-based vertical-cavity surface-emitting lasers
Open this publication in new window or tab >>Development of 1.3-μm GaAs-based vertical-cavity surface-emitting lasers
2005 (English)Doctoral thesis, comprehensive summary (Other scientific)
Abstract [en]

Long-wavelength vertical-cavity surface-emitting lasers (VCSELs) are desirable as low-cost sources for optical metropolitan-area and access networks. In the development of 1.3-µm VCSELs, most attention today is given to monolithic GaAs-based solutions, although no established active material exists in this wavelength region. This thesis investigates the possibility of reaching the 1.3-µm telecom wavelength window using GaInNAs quantum wells (QWs) or 1.2-µm InGaAs QWs in conjunction with negative gain-cavity detuning in VCSELs. The work includes metal-organic vapor-phase epitaxy and characterization of InGaAs and GaInNAs QWs, realization of 1.3-µm InGaAs VCSELs as well as elements of optimization and analysis of such lasers. The evaluation of GaInNAs and InGaAs QWs has been performed using a number of characterization methods such as photoluminescence (PL), high-resolution x-ray diffraction, secondary-ion mass spectroscopy, and atomic-force microscopy as well as fabrication and evaluation of broad-area lasers (BALs).

Both performance and growth reproducibility of GaInNAs QWs are considered and could be improved by using high V/III ratios. Nontrivial relations between PL and laser performance are pointed out and the technologically important but problematic combination of AlGaAs and GaInNAs in the same epitaxial structure is studied. Parallel to the work on GaInNAs, the possibility of extending the wavelength of InGaAs QWs towards 1.3 µm has been investigated. Generally better luminescence efficiency and laser performance are obtained for InGaAs than for GaInNAs QWs, but the gain-peak wavelength for InGaAs QWs is presently limited to about 1.24 µm due to strain-induced degradation. In this work the InGaAs QW growth is optimized for long wavelength and high luminescence. It is demonstrated that multiple QW structures can be grown with strain similar to that of single QWs, which is interesting for VCSEL applications. Record BALs with two to five InGaAs/GaAs QWs have low threshold current densities,  70 A/cm2 per QW at 1.24 µm. The main advantage of InGaAs QWs compared to GaInNAs QWs is that they represent a better-known material system with less complex and more stable growth. However, InGaAs QWs > 1.2 µm are on the verge of strain relaxation, and the possible consequences for laser production and reliability have to be considered.

Using 1.2-µm InGaAs QWs, high-performance 1.3-µm VCSELs were achieved by negative gain-cavity detuning. Dynamic performance and surface reliefs to improve the single-mode operation have been investigated. The VCSELs have excellent high-temperature performance due to a smaller spectral distance between the gain-peak and the laser mode at elevated temperature. More specifically, a 1.27-µm single-mode device showed maximum output powers of 1.1 and 0.5 mW at 20 and 140ºC, which is state-of-the-art for GaAs-based long-wavelength VCSELs.

In all, two methods for 1.3-µm GaAs-based VCSELs, GaInNAs and InGaAs QWs, have been investigated. GaInNAs is a difficult material but is still promising and several companies have predicted a near-future market introduction. However, the growth of GaInNAs is both complex and sensitive to growth fluctuations. On the other hand, gain-cavity detuned InGaAs-QW VCSELs show state-of-the-art performance at 1260-1290 nm with straightforward growth and processing. The devices exhibit good static and dynamic performance, and preliminary reliability tests indicate that there is no intrinsic problem. Both approaches are promising for application in real-world optical networks and deserve further attention.

Place, publisher, year, edition, pages
Stockholm: KTH, 2005. 65 p.
Series
Trita-HMA, ISSN 1404-0379 ; 2005:1
Keyword
Physics, Fysik
National Category
Physical Sciences
Identifiers
urn:nbn:se:kth:diva-263 (URN)
Public defence
2005-06-10, Sal C1, KTH-Elektrum, 10:00
Opponent
Supervisors
Note
QC 20101001Available from: 2005-06-07 Created: 2005-06-07 Last updated: 2010-10-01Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopushttp://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=APPLAB000086000021211109000001&idtype=cvips&gifs=Yes

Authority records BETA

Schatz, RichardHammar, Mattias

Search in DiVA

By author/editor
Chacinski, MarekSchatz, RichardKjebon, OlleHammar, MattiasMarcks von Würtemberg, RickardMogg, SebastianSundgren, PetrusBerggren, Jesper
By organisation
Microelectronics and Applied Physics, MAPOptics and PhotonicsMicroelectronics and Information Technology, IMITIntegrated Devices and Circuits
In the same journal
Applied Physics Letters
Atom and Molecular Physics and Optics

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 330 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf