Design Tradeoffs for High-Speed Directional Coupler Modulators with Δβ-Reversal in LiNbO3

1984 ◽  
Vol 5 (1) ◽  
Author(s):  
F. Auracher

SummaryWe show the tradeoffs between the bandwidth-length product, drive voltage-length product and the optical insertion-loss of modulators butt-coupled to single-mode fibers. The numerical calculations are performed for a new design that permits fast Δβ-operation of directional coupler modulators.

1984 ◽  
Vol 5 (1) ◽  
Author(s):  
F. Auracher ◽  
D. Schicketanz ◽  
K.-H. Zeitler

SummaryWe report on a very fast (≥ 6 Gbit/s) Δβ-reversal directional-coupler modulator with low insertion loss (2 dB) for 1.3 μm wavelength operation. The design of the modulator permits easy and reproducible fabrication.


2002 ◽  
Vol 722 ◽  
Author(s):  
T. S. Sriram ◽  
B. Strauss ◽  
S. Pappas ◽  
A. Baliga ◽  
A. Jean ◽  
...  

AbstractThis paper describes the results of extensive performance and reliability characterization of a silicon-based surface micro-machined tunable optical filter. The device comprises a high-finesse Fabry-Perot etalon with one flat and one curved dielectric mirror. The curved mirror is mounted on an electrostatically actuated silicon nitride membrane tethered to the substrate using silicon nitride posts. A voltage applied to the membrane allows the device to be tuned by adjusting the length of the cavity. The device is coupled optically to an input and an output single mode fiber inside a hermetic package. Extensive performance characterization (over operating temperature range) was performed on the packaged device. Parameters characterized included tuning characteristics, insertion loss, filter line-width and side mode suppression ratio. Reliability testing was performed by subjecting the MEMS structure to a very large number of actuations at an elevated temperature both inside the package and on a test board. The MEMS structure was found to be extremely robust, running trillions of actuations without failures. Package level reliability testing conforming to Telcordia standards indicated that key device parameters including insertion loss, filter line-width and tuning characteristics did not change measurably over the duration of the test.


2009 ◽  
Vol 19 (1) ◽  
pp. 47-62
Author(s):  
Adel l Zaghlou ◽  
Rasheed El-Awady ◽  
Sayed Kamel ◽  
Sohair Mahfouz

2014 ◽  
Vol 988 ◽  
pp. 544-547
Author(s):  
Guang Li

A novel high speed and ultra long-haul radio-over-fiber (ROF) system based on Dual Photoelectric Arms Coherent Modulation (DPACM) and Optical Duo-Binary Coding (ODBC) is proposed, and demonstrated. The signal spectrum bandwidth, generated by ODBC based on the first order DPACM, is half of non-return-to-zero (NRZ ) signal spectrum bandwidth. The secondary order DPACM generates a 40-GHz Millimeter-wave (mm-wave) that is transmitted over fiber (ROF). The simulation results show that, the bit rate can be up to 40 Gbps and the transmission distance is over 1500 Km, based on the ROF system with a 0 dBm continuous-wave laser source, multiple stages Er-Doped Fiber Amplifier (EDFA), a standard single mode fiber (SSMF) with a dispersion of 17 ps/nm/Km and a attenuation of 0.2 dB/Km.


2016 ◽  
Vol 30 (06) ◽  
pp. 1650063 ◽  
Author(s):  
Jingwen Sun ◽  
Jian Sun ◽  
Yunji Yi ◽  
Lucheng Qv ◽  
Shiqi Sun ◽  
...  

A low-cost and high-speed electro-optic (EO) switch using the guest–host EO material Disperse Red 1/Polymethyl Methacrylate (DR1/PMMA) was designed and fabricated. The DR1/PMMA material presented a low processing cost, an excellent photostability and a large EO coefficient of 13.1 pm/V. To improve the performance of the switch, the in-plane buried electrode structure was introduced in the polymer Mach–Zehnder waveguide to improve the poling and modulating efficiency. The characteristic parameters of the waveguide and the electrodes were carefully designed and the fabrication process was strictly controlled. Under 1550 nm, the insertion loss of the device was 12.7 dB. The measured switching rise time and fall time of the switch were 50.00 ns and 54.29 ns, respectively.


AIP Advances ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 015325
Author(s):  
Yuhong Zhou ◽  
Junqi Liu ◽  
Shenqiang Zhai ◽  
Ning Zhuo ◽  
Jinchuan Zhang ◽  
...  

2021 ◽  
Vol 11 (9) ◽  
pp. 4015
Author(s):  
Peter Hellwig ◽  
Klaus Schricker ◽  
Jean Pierre Bergmann

High processing speeds enormously enlarge the number of possible fields of application for laser processes. For example, material removal for sheet cutting using multiple passes or precise mass corrections can be achieved by means of spatter formation. For a better understanding of spatter formation at processing speeds of several hundred meters per minute, characterizations of the processing zone are required. For this purpose, a 400 W single-mode fiber laser was used in this study to process stainless steel AISI 304 (1.4301/X5CrNi18-10) with speeds of up to 600 m/min. A setup was developed that enabled a lateral high-speed observation of the processing zone by means of a glass plate flanking. This approach allowed for the measurement of several dimensions, such as the penetration depth, spatter formation, and especially, the inclination angle of the absorption front. It was shown that the loss of mass started to significantly increase when the absorption front was inclined at about 60°. In combination with precise weighings, metallographic examinations, and further external process observations, these findings provided an illustration of four empirical process models for different processing speeds.


2019 ◽  
Vol 0 (0) ◽  
Author(s):  
I. S. Amiri ◽  
P. G. Kuppusamy ◽  
Ahmed Nabih Zaki Rashed ◽  
P. Jayarajan ◽  
M. R. Thiyagupriyadharsan ◽  
...  

AbstractHigh-speed single-mode fiber-optic communication systems have been presented based on various hybrid multiplexing schemes. Refractive index step and silica-doped germanium percentage parameters are also preserved during their technological boundaries of attention. It is noticed that the connect design parameters suffer more nonlinearity with the number of connects. Two different propagation techniques have been used to investigate the transmitted data rates as a criterion to enhance system performance. The first technique is soliton propagation, where the control parameters lead to equilibrium between the pulse spreading due to dispersion and the pulse shrinking because of nonlinearity. The second technique is the MTDM technique where the parameters are adjusted to lead to minimum dispersion. Two cases are investigated: no dispersion cancellation and dispersion cancellation. The investigations are conducted over an enormous range of the set of control parameters. Thermal effects are considered through three basic quantities, namely the transmission data rates, the dispersion characteristics, and the spectral losses.


Nanophotonics ◽  
2020 ◽  
Vol 9 (16) ◽  
pp. 4743-4748
Author(s):  
Elham Heidari ◽  
Hamed Dalir ◽  
Moustafa Ahmed ◽  
Volker J. Sorger ◽  
Ray T. Chen

AbstractVertical-cavity surface-emitting lasers (VCSELs) have emerged as a vital approach for realizing energy-efficient and high-speed optical interconnects in the data centers and supercomputers. Indeed, VCSELs are the most suitable mass production lasers in terms of cost-effectiveness and reliability. However, there are still key challenges that prevent achieving modulation speeds beyond 30s GHz. Here, we propose a novel VCSEL design of a hexagonal transverse-coupled-cavity adiabatically coupled through a central cavity. Following this scheme, we show a prototype demonstrating a 3-dB roll-off modulation bandwidth of 45 GHz, which is five times greater than a conventional VCSEL fabricated on the same epiwafer structure. This design harnesses the Vernier effect to increase the laser’s aperture and therefore is capable of maintaining single-mode operation of the laser for high injection currents, hence extending the dynamic roll-off point and offering increases power output. Simultaneously, extending both the laser modulation speed and output power for this heavily deployed class of lasers opens up new opportunities and fields of use ranging from data-comm to sensing, automotive, and photonic artificial intelligence systems.


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