1.55 μm High Speed Partly Gain-Coupled DFB Lasers with Periodically  Etched Strained-Layer Quantum Wells

The high speed performance of partly gain-coupled (GC) DFB lasers consisting of periodically etched strained-layer quantum wells (QW's) is reviewed with comparisons to the equivalent index-coupled (IC) DFB lasers with the same active layers. It is shown that the GC DFB laser has a –3 dB modulation bandwidth of 22 GHz at 10 mW with a stable single mode oscillation at the longer side of the Bragg Stop-band due to in-phase gain coupling. A theoretical analysis is also presented based on the local-normal-mode transfer-matrix laser model which takes into account both the longitudinal distribution of laser parameters and carrier transport effects. The mechanism for high modulation bandwidth of the GC DFB laser is attributed to a higher differential gain due to a reduced carrier transport time which is provided by an effecient carrier injection from the longitudinal etched interface of the QW's.

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High Speed 1.55 μm Lasers for Fiber Optic Transmission

International Journal of High Speed Electronics and Systems ◽

10.1142/s0129156497000160 ◽

1997 ◽

Vol 08 (03) ◽

pp. 457-474

Author(s):

Paul A. Morton

Keyword(s):

Active Region ◽

High Speed ◽

Carrier Transport ◽

Multiple Quantum Well ◽

Optical Filter ◽

Essential Elements ◽

Laser Source ◽

Multiple Quantum ◽

Modulation Bandwidth ◽

Dfb Laser

This paper describes the essential elements for creating a practical wide bandwidth directly modulated laser source. This includes considerations of the intrinsic limitations of the laser structure, due to the resonant frequency and damping of the laser output, together with carrier transport issues to allow carriers in the device active region to be efficiently modulated at high speeds. The use of a P-doped compressively strained multiple-quantum well active region to provide high intrinsic speed and remove transport limitations is described, together with record setting results of 25 GHz modulation bandwidth for a 1.55 μm Fabry–Perot laser and 26 GHz bandwidth for a 1.55 μm DFB laser. The challenges of providing high bandwidth electrical connections to the laser on a suitable submount, together with fiber attachment and microwave packaging are discussed. Results of fully packaged 1.55 μm DFB laser with 25 GHz modulation bandwidth are shown. Digital modulation of the packaged 1.55 μm DFB including impedance matching is described, and the transient wavelength chirp is presented. This low chirp is reduced further using an optical filter, to provide a 10 GBit/s source that can transmit error free over 38.5 km of standard optical fiber.

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Polymer colour converter with very high modulation bandwidth for visible light communications

Journal of Materials Chemistry C ◽

10.1039/c7tc03787b ◽

2017 ◽

Vol 5 (35) ◽

pp. 8916-8920 ◽

Cited By ~ 7

Author(s):

D. A. Vithanage ◽

A. L. Kanibolotsky ◽

S. Rajbhandari ◽

P. P. Manousiadis ◽

M. T. Sajjad ◽

...

Keyword(s):

Visible Light ◽

High Speed ◽

Visible Light Communication ◽

Modulation Bandwidth ◽

Visible Light Communications ◽

Semiconducting Polymer ◽

High Modulation ◽

Very High

We report the synthesis, photophysics and application of a novel semiconducting polymer as a colour converter for high speed visible light communication.

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1.55 μm HIGH SPEED PARTLY GAIN-COUPLED DFB LASERS WITH PERIODICALLY ETCHED STRAINED-LAYER QUANTUM WELLS

Selected Topics in Electronics and Systems - High Speed Diode Lasers ◽

10.1142/9789812816863_0004 ◽

1998 ◽

pp. 99-118

Author(s):

TOSHIHIKO MAKINO

Keyword(s):

Quantum Wells ◽

High Speed ◽

Strained Layer

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High-Speed Carrier-Injection-Based Polarization Controller With InGaAlAs/InAlAs Multiple-Quantum Wells

IEEE Photonics Technology Letters ◽

10.1109/lpt.2017.2757526 ◽

2017 ◽

Vol 29 (22) ◽

pp. 1951-1954 ◽

Cited By ~ 7

Author(s):

Mohiyuddin Kazi ◽

Samir Ghosh ◽

Hassanet Sodabanlu ◽

Kentaro Suzuki ◽

Masakazu Sugiyama ◽

...

Keyword(s):

Quantum Wells ◽

High Speed ◽

Polarization Controller ◽

Multiple Quantum Wells ◽

Multiple Quantum ◽

Carrier Injection

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Broadband high-efficiency near-infrared graphene phase modulators enabled by metal–nanoribbon integrated hybrid plasmonic waveguides

Nanophotonics ◽

10.1515/nanoph-2021-0709 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Longfang Ye ◽

Kouxiang Yuan ◽

Chunhui Zhu ◽

Yao Zhang ◽

Yong Zhang ◽

...

Keyword(s):

Energy Consumption ◽

Phase Modulation ◽

High Speed ◽

Near Infrared ◽

High Efficiency ◽

Modulation Bandwidth ◽

Plasmonic Waveguides ◽

Phase Modulators ◽

High Modulation ◽

Hybrid Plasmonic Waveguides

Abstract The phase modulator is a key component in optical communications for its phase modulation functions. In this paper, we numerically demonstrate a variety of ultra-compact high-efficiency graphene phase modulators (GPMs) based on metal–nanoribbon integrated hybrid plasmonic waveguides in the near-infrared region. Benefiting from the good in-plane mode polarization matching and strong hybrid surface plasmon polariton and graphene interaction, the 20 μm-length GPM can achieve excellent phase modulation performance with a good phase and amplitude decoupling effect, a low insertion loss around 0.3 dB/μm, a high modulation efficiency with V π L π of 118.67 V μm at 1.55 μm, which is 1–3 orders improvement compared to the state-of-the-art graphene modulators. Furthermore, it has a wide modulation bandwidth of 67.96 GHz, a low energy consumption of 157.49 fJ/bit, and a wide operating wavelength ranging from 1.3 to 1.8 μm. By reducing the overlap width of the graphene–Al2O3–graphene capacitor, the modulation bandwidth and energy consumption of the modulator can be further improved to 370.36 GHz and 30.22 fJ/bit, respectively. These compact and energy-efficient GPMs may hold a key to various high-speed telecommunications, interconnects, and other graphene-based integrated photonics applications.

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Neuro-Inspired Computing with Spin-VCSELs

Applied Sciences ◽

10.3390/app11094232 ◽

2021 ◽

Vol 11 (9) ◽

pp. 4232

Author(s):

Krishan Harkhoe ◽

Guy Verschaffelt ◽

Guy Van der Sande

Keyword(s):

Processing Speed ◽

Delay Time ◽

High Speed ◽

State Of The Art ◽

Polarization Modulation ◽

Time Interval ◽

Computing Technique ◽

High Modulation ◽

Short Time ◽

Modulation Speed

Delay-based reservoir computing (RC), a neuromorphic computing technique, has gathered lots of interest, as it promises compact and high-speed RC implementations. To further boost the computing speeds, we introduce and study an RC setup based on spin-VCSELs, thereby exploiting the high polarization modulation speed inherent to these lasers. Based on numerical simulations, we benchmarked this setup against state-of-the-art delay-based RC systems and its parameter space was analyzed for optimal performance. The high modulation speed enabled us to have more virtual nodes in a shorter time interval. However, we found that at these short time scales, the delay time and feedback rate heavily influence the nonlinear dynamics. Therefore, and contrary to other laser-based RC systems, the delay time has to be optimized in order to obtain good RC performances. We achieved state-of-the-art performances on a benchmark timeseries prediction task. This spin-VCSEL-based RC system shows a ten-fold improvement in processing speed, which can further be enhanced in a straightforward way by increasing the birefringence of the VCSEL chip.

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Asymmetric Ge/SiGe coupled quantum well modulators

Nanophotonics ◽

10.1515/nanoph-2021-0007 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1765-1773

Author(s):

Yi Zhang ◽

Jianfeng Gao ◽

Senbiao Qin ◽

Ming Cheng ◽

Kang Wang ◽

...

Keyword(s):

Energy Consumption ◽

Quantum Well ◽

Quantum Wells ◽

High Speed ◽

Low Voltage ◽

Extinction Ratio ◽

High Frequency Response ◽

Modulation Format ◽

Silicon Photonic ◽

Coupled Quantum Well

Abstract We design and demonstrate an asymmetric Ge/SiGe coupled quantum well (CQW) waveguide modulator for both intensity and phase modulation with a low bias voltage in silicon photonic integration. The asymmetric CQWs consisting of two quantum wells with different widths are employed as the active region to enhance the electro-optical characteristics of the device by controlling the coupling of the wave functions. The fabricated device can realize 5 dB extinction ratio at 1446 nm and 1.4 × 10−3 electrorefractive index variation at 1530 nm with the associated modulation efficiency V π L π of 0.055 V cm under 1 V reverse bias. The 3 dB bandwidth for high frequency response is 27 GHz under 1 V bias and the energy consumption per bit is less than 100 fJ/bit. The proposed device offers a pathway towards a low voltage, low energy consumption, high speed and compact modulator for silicon photonic integrated devices, as well as opens possibilities for achieving advanced modulation format in a more compact and simple frame.

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Fast speed switching response and high modulation signal processing bandwidth through LiNbO3 electro-optic modulators

Journal of Optical Communications ◽

10.1515/joc-2020-0012 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Mahmoud M. A. Eid ◽

Ahmed Nabih Zaki Rashed ◽

Iraj S. Amiri

Keyword(s):

Near Infrared ◽

Infrared Region ◽

Modulation Bandwidth ◽

Fast Speed ◽

Electrooptic Modulators ◽

High Modulation ◽

Data Rates ◽

Electro Optic ◽

Modulation Signal ◽

Speed Response

AbstractThis work outlined the fast speed response and high modulation bandwidth through LiNbO3 electro-optic modulators. The refractive index is analyzed to estimate the switching voltage and modulation bandwidth for these modulators. The modulation voltage and data transmission data rates are analyzed and discussed clearly through LiNbO3 electro-optic modulators. The modulator’s performance efficiency is upgraded with the optimum modulator length of 10 mm and its thickness of 2 mm. The proposed modulators are compared with GaAs electrooptic modulators under various electro-optic modulators dimensions at 1300 nm near-infrared region and room temperature.

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