Single‐Mode, High‐Brightness, and High‐Speed VCSEL Arrays

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.

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High-speed operation of single-mode tunable quantum cascade laser based on ultra-short resonant cavity

AIP Advances ◽

10.1063/5.0036219 ◽

2021 ◽

Vol 11 (1) ◽

pp. 015325

Author(s):

Yuhong Zhou ◽

Junqi Liu ◽

Shenqiang Zhai ◽

Ning Zhuo ◽

Jinchuan Zhang ◽

...

Keyword(s):

Quantum Cascade Laser ◽

High Speed ◽

Resonant Cavity ◽

Single Mode ◽

Quantum Cascade

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Investigations of the Absorption Front in High-Speed Laser Processing Up to 600 m/min

Applied Sciences ◽

10.3390/app11094015 ◽

2021 ◽

Vol 11 (9) ◽

pp. 4015

Author(s):

Peter Hellwig ◽

Klaus Schricker ◽

Jean Pierre Bergmann

Keyword(s):

High Speed ◽

Glass Plate ◽

Single Mode ◽

Single Mode Fiber ◽

Process Models ◽

External Process ◽

Steel Aisi ◽

Loss Of Mass ◽

Processing Zone ◽

High Processing

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.

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The Engagement of Hybrid Ultra High Space Division Multiplexing with Maximum Time Division Multiplexing Techniques for High-Speed Single-Mode Fiber Cable Systems

Journal of Optical Communications ◽

10.1515/joc-2019-0205 ◽

2019 ◽

Vol 0 (0) ◽

Author(s):

I. S. Amiri ◽

P. G. Kuppusamy ◽

Ahmed Nabih Zaki Rashed ◽

P. Jayarajan ◽

M. R. Thiyagupriyadharsan ◽

...

Keyword(s):

Communication Systems ◽

High Speed ◽

Single Mode ◽

Single Mode Fiber ◽

Design Parameters ◽

Control Parameters ◽

Data Rates ◽

Fiber Optic Communication ◽

High Space ◽

Optic Communication

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.

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Hexagonal transverse-coupled-cavity VCSEL redefining the high-speed lasers

Nanophotonics ◽

10.1515/nanoph-2020-0437 ◽

2020 ◽

Vol 9 (16) ◽

pp. 4743-4748

Author(s):

Elham Heidari ◽

Hamed Dalir ◽

Moustafa Ahmed ◽

Volker J. Sorger ◽

Ray T. Chen

Keyword(s):

High Speed ◽

Single Mode ◽

Cavity Surface ◽

Surface Emitting Lasers ◽

Vertical Cavity Surface ◽

Emitting Lasers ◽

Injection Currents ◽

Vertical Cavity ◽

Coupled Cavity ◽

Modulation Speed

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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