Optimization of the carrier-induced effective index change in InGaAsP waveguides-application to tunable Bragg filters

Weber, J.-P.

doi:10.1109/3.301645

Cited by 144 publications

(78 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

Section: Band Filling and Bandgap Shrinkagementioning

confidence: 99%

“…The temperature dependence of the index of refraction can be modeled for InGaAsP based materials using (2-28). Where the high frequency dielectric constant is given by (2-29) as a function of the y parameter and it's variation with temperature is given by (2-30) [21] ^■(7dr (7 '~3 00) )…”

Section: Thermal Compensationmentioning

confidence: 99%

“…For tuning efficiency the thermal resistivity can be an important parameter and this depends on the alloy composition according to (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22). …”

Section: Other Materials Parametersmentioning

confidence: 99%

“…The bands are filled as the bandgap shrinks so these two effects must be treated together. For a direct bandgap semiconductor with parabolic bands the absorption spectrum is given by (2-17) neglecting the Urbachtail [21].The absorption constant C depends on the material and can be estimated for In^xGaxASyPi.y materials lattice matched to InP (x « 0.47y) using (2-18).The absorption coefficient for a semiconductor with carrier injection is given by (2-19).If we consider the contributions from the light holes and heavy holes separately the change in absorption can be given by (2-20).The AE g term has been included to account for the band gap shrinkage effect. Which can be modeled using (2-21).…”

mentioning

confidence: 99%

See 3 more Smart Citations

Improved Sampled Grating DBR Widely-Tunable 1.55 micrometer-Lasers

Mason¹,

Barton²,

Coldren³

2000

View full text Add to dashboard Cite

Over the last three years, a number of improvements have been made in the design of SGDBR lasers with integrated componentry. Device design has improved the output power and tuning range due to an increase in the number of quantum wells in the active region from four to six. Devices with up to 8 mW of output power with integrated amplifiers and buried heterostructure devices with 72 nm tuning ranges were realized. Current laser results indicate that leakage current in buried heterostructure lasers is a major factor in limiting the device performance. To eliminate the parasitic leakage paths we have begun to investigate Fe doped blocking junctions for the device. Work on the wavelength monitor has focused on an external approach, which uses a wavelength dependent coupler in conjunction with a pair of photodetectors. Initial results show better than 1 nm sensitivity over a 30 nm range. The most recent work on the laser has focussed on integrating additional components for increased functionality. We have developed a curved waveguide semiconductor optical amplifier that can be integrated with the laser to increase the output power to greater than 6 mW.We have also investigated SGDBR lasers with integrated electro-absorption modulators. Using a 300 urn long bulk EA modulator we have demonstrated error free data transmission at 2.5 GBit/s with a 2 3I -1 pattern length at received powers of-32.5 dBm. Subject termsSemiconductor lasers, photonic integrated circuits, wavelength monitors, WDM devices, semiconductor optical amplifiers, electro-absorption modulators IntroductionThe goal of this program was to develop a widely tunable semiconductor laser diode with an integrated wavelength monitor. The widely tunable laser is a four section device with a pair of sampled grating distributed Bragg reflector mirrors as shown in figure 1. These devices use a Vernier effect tuning mechanism to provide widely tunable wavelength ranges. Because of the simple offset waveguide design, SGDBR lasers are easily integrated with other optoelectronic devices such as wavelength monitors, optical amplifiers, and modulators to form photonic integrated circuits. They employ periodically sampled grating mirrors which have multiple reflection peaks spaced approximately 5-7 nm apart. The duty cycle and sampling periods have been optimized for the desired wavelength coverage. A phase control section is included to enable alignment of the cavity mode with the mirror reflection peaks. Devices were fabricated using both ridge and buried ridge waveguide processes with passive regions formed by a combination of etching and MOCVD regrowth.This work is discussed in detail in Dr. T.G.B Mason's dissertation -which is included as Appendix I. Supplementary material outlining work on semiconductor optical amplifiers (SOAs) and Electro-absorption modulators (EAM) is also included in the report. Thesis summaryFirst we will briefly summarize the key results from Dr. Mason's dissertation. In appendix I, Dr. Mason discusses the design and development of ph...

show abstract

Section: Band Filling and Bandgap Shrinkagementioning

confidence: 99%

Section: Thermal Compensationmentioning

confidence: 99%

Section: Other Materials Parametersmentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Improved Sampled Grating DBR Widely-Tunable 1.55 micrometer-Lasers

Mason¹,

Barton²,

Coldren³

2000

View full text Add to dashboard Cite

show abstract

“…The first term in (2) quantifies the effect of free carriers on the refractive index of the material [12] that is mainly intended in FCI tuning. The next two terms describe the temperature-induced change in index that is an unintended consequence of the current flow in the device.…”

mentioning

confidence: 99%

Carrier-induced refractive index changes in InP-based circular microresonators for low-voltage high-speed modulation

Sadagopan

Choi

Djordjev

et al. 2005

IEEE Photon. Technol. Lett.

View full text Add to dashboard Cite

Abstract-Optical InP-based microresonator modulators which achieve low-voltage high-bandwidth modulation are presented, where resonant wavelength tuning of a circular resonator by free carrier injection is used as the modulation mechanism. Since thermal effects in small resonant cavities and switching speed limitations posed by minority carrier lifetime are the primary concerns in such types of devices, ion bombardment in microtoroidal structures is used to increase the speed of response. The modulation speed is enhanced by an order of magnitude. . In these devices, free carriers injected into the intrinsic region change the effective index of the whispering gallery modes (WGMs), and thus, blue-shift the resonant wavelengths in the spectral range of interest. Although other modulation mechanisms such as electroabsorption, depletion, and gain have been demonstrated [5], [6], we focus in this letter on the FCI mechanism as it is an attractive candidate to achieve low-voltage modulation in the InP-based material system. Index Terms-HighA current limitation of these devices is their limited high-frequency response which is controlled by the minority carrier lifetime. Also, these devices exhibit thermal tuning under forward bias that limits their performance. In this letter, we demonstrate greater than an order of magnitude improvement in the operation bandwidth of FCI modulators through the use of proton implantation to reduce the minority carrier lifetime in these devices [7]. Low voltage operation is maintained by instituting fabrication approaches that improve the sensitivity of the ion implanted devices. We will also present a model of the tuning mechanism including the effects of both FCI and thermal effects that quantifies the speed-voltage swing tradeoff in these devices. The principle of operation of the FCI modulator involves the resonant transfer of optical energy between two waveguides at the resonance of a microresonator that couples them. An example of such a coupling structure is shown in Fig. 1. Modulation of light in the through port is accomplished by rapid tuning of the index of refraction and, thus, the resonant frequency of the microresonator by FCI.The microresonator modulators in our study are fabricated with a combination of epitaxial growth and wafer bonding using a process that has been described in previous publications [1], [5], [8]. Some modifications have been introduced to maintain the small bias swing necessary to operate the modulator modified by the ion implantation process. Device fabrication starts with the growth of the epi-structure that contains the disk core with a sacrificial InGaAsP layer on top that will be removed after the ion implantation. This structure is bombarded with protons to achieve lifetime reduction. Protons with energy of 40 keV were chosen so as to cause maximum damage at the center of the disk waveguide core layer. After the ion implantation, the sacrificial layer is removed to provide a relatively defect free growth interface for the rest of the epitaxial st...

show abstract

Integrated phased‐array switches for large‐scale photonic routing on chip

Soğancı

Tanemura

Nakano

2012

Laser & Photonics Reviews

View full text Add to dashboard Cite

Integrated phased‐array optical switches, having a high port‐count scalability and broad spectral coverage, can potentially be used as building blocks of large‐scale optical routers. In this article, recent works on monolithically integrated InP phased‐array switches and their applications to optical packet switching (OPS) are reviewed. After describing the theory of integrated phased‐array switches, experimental results on a single‐stage 1 × 16 switch, which features wavelength‐independent nanosecond switching characteristics, are presented. A series of OPS experiments, employing high‐bit‐rate optical packets with different modulation formats and a tunable optical buffering experiment are presented as potential applications of these switches. Finally, a large‐scale monolithic switch with as many as 100 ports is realized on a single photonic integrated circuit by cascading the phased‐array switches.

show abstract

Optimization of the carrier-induced effective index change in InGaAsP waveguides-application to tunable Bragg filters

Cited by 144 publications

References 27 publications

Improved Sampled Grating DBR Widely-Tunable 1.55 micrometer-Lasers

Improved Sampled Grating DBR Widely-Tunable 1.55 micrometer-Lasers

Carrier-induced refractive index changes in InP-based circular microresonators for low-voltage high-speed modulation

Integrated phased‐array switches for large‐scale photonic routing on chip

Contact Info

Product

Resources

About