| 1. |
- Wang, Shu Min, 1963, et al.
(författare)
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Growth of dilute nitrides and 1.3 μm edge emitting lasers on GaAs by MBE
- 2011
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Ingår i: Physica Status Solidi (B): Basic Research. - : Wiley. - 1521-3951 .- 0370-1972. ; 248:5, s. 1207-1211
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we report recent progresses on growth of dilute nitrides and 1.3 mu m lasers on GaAs using molecular beam epitaxy at Chalmers University of Technology, Sweden. Intense long wavelength light emission up to 1.71 mu m at room temperature has been achieved by using the N irradiation method and the low growth rate. It is also demonstrated that incorporation of N in relaxed InGaAs buffer grown on GaAs strongly enhances the optical quality of metamorphic InGaAs quantum wells. With the optimized growth conditions and the laser structures, we demonstrate 1.3 mu m GaInNAs edge emitting lasers on GaAs with state-of-the-art performances including a low threshold current density, a high-characteristic temperature, a 3 dB bandwidth of 17 GHz and uncooled operation at 10 Gbit/s up to 110 degrees C. The laser performances are comparable with the best reported data from the InGaAsP lasers on InP and is superior to the InAs quantum dot lasers on GaAs.
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| 2. |
- Baveja, P. P., et al.
(författare)
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Assessment of VCSEL thermal rollover mechanisms from measurements and empirical modeling
- 2011
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Ingår i: Optics Express. - 1094-4087 .- 1094-4087. ; 19:16, s. 15490-15505
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Tidskriftsartikel (refereegranskat)abstract
- We use an empirical model together with experimental measurements for studying mechanisms contributing to thermal rollover in vertical-cavity surface-emitting lasers (VCSELs). The model is based on extraction of the temperature dependence of threshold current, internal quantum efficiency, internal optical loss, series resistance and thermal impedance from measurements of output power, voltage and lasing wavelength as a function of bias current over an ambient temperature range of 15-100 degrees C. We apply the model to an oxide-confined, 850-nm VCSEL, fabricated with a 9-mu m inner-aperture diameter and optimized for highspeed operation, and show for this specific device that power dissipation due to linear power dissipation (sum total of optical absorption, carrier thermalization, carrier leakage and spontaneous carrier recombination) exceeds power dissipation across the series resistance (quadratic power dissipation) at any ambient temperature and bias current. We further show that the dominant contributors to self-heating for this particular VCSEL are quadratic power dissipation, internal optical loss, and carrier leakage. A rapid reduction of the internal quantum efficiency at high bias currents (resulting in high temperatures) is identified as being the major cause of thermal rollover. Our method is applicable to any VCSEL and is useful for identifying the mechanisms limiting the thermal performance of the device and to formulate design strategies to ameliorate them.
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| 3. |
- Davani, Hooman A., et al.
(författare)
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Widely Electro Thermal Tunable Bulk-Micromachined MEMS-VCSEL Operating Around 850nm
- 2011
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Ingår i: Conference on Lasers and Electro-Optics/Pacific Rim, CLEOPR 2011; Sydney; Australia; 28 August 2011 through 1 September 2011. - 2162-2701. - 9780977565771 ; , s. 32-34
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Konferensbidrag (refereegranskat)abstract
- We present the highest reported continues tuning range of 37 nm and fastest electro thermal tuning speed of 700 Hz achieved with tunable vertical-cavity surface-emitting lasers (VCSEL) and semiconductor DBRs at 850 nm wavelength range.
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| 4. |
- Gierl, Christian, et al.
(författare)
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Tuneable VCSEL aiming for the application in interconnects and short haul systems
- 2011
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Ingår i: Proceedings of SPIE - The International Society for Optical Engineering. - : SPIE. - 0277-786X .- 1996-756X. - 9780819484963 ; 7959
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Widely tunable vertical cavity surface emitting lasers (VCSEL) are of high interest for optical communications, gas spectroscopy and fiber-Bragg-grating measurements. In this paper we present tunable VCSEL operating at wavelength around 850 nm and 1550 nm with tuning ranges up to 20 nm and 76 nm respectively. The first versions of VCSEL operating at 1550 nm with 76 nm tuning range and an output power of 1.3mW were not designed for high speed modulation, but for applications where only stable continious tuning is essential (e.g. gas sensing). The next step was the design of non tunable VCSEL showing high speed modulation frequencies of 10 GHz with side mode supression ratios beyond 50 dB. The latest version of these devices show record output powers of 6.7mW at 20 °C and 3mW at 80 °C. The emphasis of our present and future work lies on the combination of both technologies. The tunable VCSEL operating in the 850 nm-region reaches a modulation bandwidth of 5.5GHz with an output power of 0.8mW.
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| 5. |
- Haglund, Erik, 1985, et al.
(författare)
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Low Spectral Width High-Speed VCSELs
- 2011
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Ingår i: International Nano-Optoelectronic Workshop (iNOW).
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The transmission distance of high-speed multimode 850 nm VCSELs is currently limited by modal dispersion. A design and process to fabricate high-speed VCSELs with a reduced spectral width using a surface relief technique are presented.
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| 6. |
- Ingham, J.D., et al.
(författare)
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32 Gb/s multilevel modulation of an 850 nm VCSEL for next-generation datacommunication standards
- 2011
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Ingår i: 2011 Conference on Lasers and Electro-Optics, CLEO 2011; Baltimore, MD; 1 May 2011 through 6 May 2011. - Washington, D.C. : OSA. - 2162-2701. - 9781557529107
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Konferensbidrag (refereegranskat)abstract
- An 850 nm vertical-cavity surface-emitting laser is modulated at 32 Gb/s using pulseamplitude modulation with four levels. Transmitter predistortion generates an optimized modulation waveform, which requires a receiver bandwidth of only 15 GHz.
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| 7. |
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| 8. |
- Kögel, Benjamin, 1979, et al.
(författare)
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Integrated MEMS-tunable VCSELs with high modulation bandwidth
- 2011
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Ingår i: Electronics Letters. - : Institution of Engineering and Technology (IET). - 1350-911X .- 0013-5194. ; 47:13, s. 764-756
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Tidskriftsartikel (refereegranskat)abstract
- The modulation bandwidth of micromachined tunable VCSELs is typically limited by the parasitic capacitance associated with the large mesa platform for the movable mirror. Presented is a simple technology for wafer-scale integration of tunable VCSELs with low mesa capacitance and high modulation bandwidth. Small signal measurements show a 3dB bandwidth of up to 6 GHz over a tuning range of 18 nm. Digital modulation is demonstrated with error-free data transmission at 5 Gbit/s and eye diagrams at 10 Gbit/s.
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| 9. |
- Kögel, Benjamin, 1979, et al.
(författare)
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Singlemode tunable VCSELs with integrated MEMS technology
- 2011
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Ingår i: European Conference on Laser and Electro-Optics (CLEO/Europe).
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Konferensbidrag (refereegranskat)abstract
- A simple MEMS technology for wafer-scale integration of short-wavelength tunable VCSELs is presented. Using a 3D model the half-symmetric cavity is optimized for singlemode emission from 10 μm large apertures over 12 nm tuning range.
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| 10. |
- Larsson, Anders, 1957, et al.
(författare)
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High speed VCSELs for short reach communication
- 2011
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Ingår i: Semiconductor Science and Technology. - 1361-6641 .- 0268-1242. ; 26:1, s. 014017-1-5-
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Tidskriftsartikel (refereegranskat)abstract
- We present the design of a high-speed 850 nm multimode vertical cavity surface-emitting laser (VCSEL) and demonstrate record performance in terms of small signal modulation bandwidth (23 GHz) and error-free operation at high bit rates (40 Gb s−1). The large bandwidth was enabled by an active region design for large differential gain and small gain compression, a low reflectivity top mirror for photon lifetime reduction and multiple oxide layers for a reduction of the capacitance. Error-free operation at 40 Gb s−1 was achieved in a back-to-back configuration with less than 0 dBm of received optical power.
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