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排序方式: 共有171条查询结果,搜索用时 15 毫秒
1.
Moeyersoon B. Morthier G. Bockstaele R. Baets R. 《Photonics Technology Letters, IEEE》2005,17(10):2032-2034
We show that the wavelength switching behavior of semiconductor tunable lasers can be improved through optical feedback from a stable reference filter. The filter is based on a novel prism-based implementation of a Fox-Smith resonator and has a response consisting of periodically spaced peaks, both in reflection and transmission. The improvement of the wavelength switching behavior stems from the suppression of the thermally induced wavelength drift associated with the switching of the tuning currents. 相似文献
2.
An analysis is made of longitudinal effects in semiconductor lasers with low facet reflectivities. For this purpose, a self-consistent model is used based on the beam propagation method, which takes into account both the lateral and longitudinal dimension. The calculations show that longitudinal effects have a significant influence on the output fields in the laser. 相似文献
3.
Experimental results on adiabatic coupling into SOI photonic Crystal coupled-cavity waveguides 总被引:1,自引:0,他引:1
P. Sanchis J. Marti W. Bogaerts P. Dumon D. Van Thourhout R. Baets 《Photonics Technology Letters, IEEE》2005,17(6):1199-1201
The experimental implementation of an adiabatic coupling technique for efficient coupling between photonic crystal single-line defect waveguides and coupled-cavity waveguides is reported. The samples were fabricated in a silicon-on-insulator substrate using 248-nm-deep ultraviolet lithography. Experimental results are compared with three-dimensional (3-D) finite-difference time-domain simulations. Furthermore, the discrepancies between two-dimensional and 3-D simulation results are analyzed. 相似文献
4.
The influence of lateral carrier diffusion and surface recombination on the self-imaging properties of semiconductor-optical-amplifier-based multimode interference couplers has been verified by simulations using a beam propagation method. It shows a significant degradation of the self-imaging properties of these devices. Buried heterostructures or deeply etched waveguide structures can decrease the impact when the degree of surface recombination is sufficiently low. 相似文献
5.
Van Laere F. Bogaerts W. Dumon P. Roelkens G. Van Thourhout D. Baets R. 《Lightwave Technology, Journal of》2009,27(5):612-618
We report on compact focusing polarization diversity grating couplers in silicon-on-insulator, which can be used to overcome the polarization dependence of nanophotonic integrated circuits. The minimum fiber-to-fiber polarization dependent loss is 0.4 dB and the focusing grating couplers are as performant as standard 2-D-grating couplers without focusing. In addition, the focusing property of the gratings results in an 8-fold length reduction of the coupling structure as compared to standard nonfocusing 2-D-grating versions. 相似文献
6.
G. Vecchi F. Raineri I. Sagnes K.-H. Lee S. Guilet L. Le Gratiet F. Van Laere G. Roelkens D. Van Thourhout R. Baets A. Levenson R. Raj 《Electronics letters》2007,43(6):39-40
An InP/InGaAs-based photonic band-edge laser bonded on silicon operating near 1.55 mum is presented. A gold reflector positioned below the slab containing the active layer reduces the optical losses of the Bloch-mode resonator. As a result, a quality factor exceeding 8000 is obtained at transparency leading to a laser threshold as low as 3.4 muJ/cm2 相似文献
7.
D'Oosterlinck W. Buron J. Ohman F. Morthier G. Baets R. 《Photonics Technology Letters, IEEE》2007,19(7):489-491
We report on the dynamic all-optical flip-flop (AOFF) operation of an optical feedback scheme consisting of a semiconductor optical amplifier (SOA) and a distributed feedback laser diode (DFB-LD), bidirectionally coupled to each other. The operation of the AOFF relies on the interplay between the optical powers in both the DFB-LD and the SOA. Switching times as low as 150ps for switch pulse energies of around 6 pJ and a repetition rate of 500MHz have been measured. The contrast ratio was measured to be above 12 dB 相似文献
8.
Ying-Tung Chen Kris Naessens Roel Baets Yunn-Shiuan Liao Ampere A. Tseng 《Optical Review》2005,12(6):427-441
For many years, the development of effective ablation or laser machining techniques for making micro-optical components has
been the key factor in the birth of new photonic devices and systems. In this article, the ablation characteristics of two
types of the most important transparent materials, transparent polymers and glasses, are studied. Simple shaped microcavities
are first machined for studying the fundamental ablation parameters, including threshold fluence, effective absorption coefficient,
and ablation rate. In studying polymer ablation, five standard grades and five proprietary polymeric compounds are selected.
Ablation techniques using these transparent polymers for making arrayed ferrules and curved microlenses are presented. Applications
of these ablated microstructures for optical fiber connectors, optical fiber coupling and alignment, and transparent chip
encapsulants, are introduced and demonstrated with emphasis on the quality of the ablated profiles and dimensions to satisfy
the required performance. In glass ablation, borosilicate glasses are considered and their associated ablation behaviors are
studied. The procedures to ablate glass-based arrayed microstructures with flat and curved surfaces are described. The utilizations
of these arrayed microstructures for optical waveguide, wave absorber, and beam guider, are specifically discussed. Finally,
concluding remakes for future trends are presented. 相似文献
9.
10.
This paper presents a general discussion on the control of widely tunable super structure grating distributed Bragg reflector (SSG-DBR) lasers. A feedback control scheme is presented that ensures frequency stability and accuracy (better than ±0.5 GHz), as well as high side mode suppression ratio (>35 dB). The active section voltage is monitored to maintain mode stability and a highly stable Fabry-Perot etalon is used as a reference to lock the laser frequency to a specific ITU channel. It is shown that stability can even be maintained when directly modulating the laser at 1.244 Gb/s. Furthermore, a characterization scheme is demonstrated that uses the voltage monitoring to generate a look-up table of operation points very efficiently and accurately. For all operation points, the frequency accuracy is better than ±0.5 GHz and the side mode suppression ratio is above 35 dB 相似文献