Nanophotonics Pioneer: Prof. Dr. Dieter Bimberg ‘Green Photonics Networks: From VCSELs to Nanophotonics

A special issue of Photonics (ISSN 2304-6732).

Deadline for manuscript submissions: closed (31 January 2023) | Viewed by 32652

Special Issue Editors


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Guest Editor
Department of Electrical Engineering, National Central University, Taoyuan City 32054, Taiwan
Interests: high-brightness/high-speed VCSEL array for 3D sensing; high-speed VCSELs for data communications; high-speed III-nitride LEDs for VLC and POF communications; high-speed photodiode/avalanche photodiode for fiber communications, high-speed/high-power photodiode for THz applications
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Guest Editor
Department of Photonics and Institute of Electro-Optical Engineering, College of Electrical and Computer Engineering, National Yang Ming Chiao Tung University, Hsinchu 30050, Taiwan
Interests: surface plasmon polariton nanolasers; perovskite lasers; microcavity polariton lasers; photonic crystal surface emitting lasers; GaN-based VCSELs

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Guest Editor
Photonics Integration System Research Center, Tokyo Institute of Technology, Tokyo, Japan
Interests: optoelectronics; VCSEL; optical interconnect; optical sensing; laser processing

Special Issue Information

Dear Colleagues,

We would like to celebrate Prof. Bimberg’s 80th birthday on 10 July 2022 through the publication of this Special Issue. Prof. Bimberg is one of the great pioneers in the field of nanophotonics, having contributed decisively over many decades to the nanomaterials and nanophotonics community. He is an inspiration for those who are just beginning their professional association with these fields as well as for present researchers. His work represents remarkable discoveries on their growth and the physics behind nanostructures. Based on these fundamental discoveries, he has developed many novel concepts for photonic and electronic devices, including high-speed QD- and QW-based VCSELs that are significantly improving the energy efficiency of data communication.

The market of data communication is booming. Compared with the traditional telecommunication market, the required link distances of less than 2 km are much shorter here, and data at the highest bit rates can be transmitted across fibers without serious limitations through chromatic dispersion or propagation loss. In these applications, the major concern regarding transmitters is their electrical-to-optical conversion loss under high-speed operation. In 2011, Prof. Bimberg and his research team world were the first to demonstrate that VCSEL can have an extremely low energy-to-data ratio (50 fJ/bit) for data communication.  This unprecedented breakthrough prompted the resurgence of the concept of VCSELs emitting in the near infrared.

Further, high-power VCSELs and tunable VCSELs are emerging as killer applications for sensing, such as structured light and time-of-flight lidar and optical coherence tomography (OCT). Due to the small cavity length and distributed Bragg reflectors, VCSELs exhibit much smaller wavelength drifts upon temperature variations. Compared with their edge-emitting counterparts, VCSELs can be tested on wafer and can be directly integrated with driver circuits or external cavity MEMS mirrors in a vertical direction for wideband (>100 nm) and mode-hop free continuous wavelength sweeping.

The purpose of this Special Issue is to highlight recent progress on VCSELs and their integration with nanophotonic structures and drivers. Original research articles and reviews are welcome. Research areas may include (but are not limited to) the following:

  1. High-speed VCSELs for data communication;
  2. High-power and high-speed VCSELs (arrays) for sensing and optical wireless communication;
  3. Tunable VCSELs;
  4. Blue/UV VCSELs;
  5. SWIR/MWIR VCSELs;
  6. QD VCSELs;
  7. Integration with nanophotonic structures;
  8. Driver integration.

We look forward to receiving your contributions.

Prof. Dr. Jin-wei Shi
Prof. Dr. Tien-Chang Lu
Prof. Dr. Fumio Koyama
Guest Editors

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Keywords

  • high-speed VCSELs
  • high-power VCSELs
  • tunable VCSELs
  • blue/UV VCSELs
  • SWIR/MWIR VCSELs
  • integration with drivers and nanophotonics
  • nanophotonic materials and devices

  • QD-lasers and amplifiers

Published Papers (13 papers)

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Editorial

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3 pages, 180 KiB  
Editorial
Nanophotonics Pioneer: Prof. Dr. Dieter Bimberg “Green Photonic Network: From VCSELs to Nanophotonics
by Jin-Wei Shi, Tien-Chang Lu and Fumio Koyama
Photonics 2023, 10(9), 976; https://doi.org/10.3390/photonics10090976 - 27 Aug 2023
Viewed by 834
Abstract
We would like to celebrate Prof [...] Full article

Research

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15 pages, 3483 KiB  
Article
Impact of Device Topology on the Performance of High-Speed 1550 nm Wafer-Fused VCSELs
by Andrey Babichev, Sergey Blokhin, Andrey Gladyshev, Leonid Karachinsky, Innokenty Novikov, Alexey Blokhin, Mikhail Bobrov, Yakov Kovach, Alexander Kuzmenkov, Vladimir Nevedomsky, Nikolay Maleev, Evgenii Kolodeznyi, Kirill Voropaev, Alexey Vasilyev, Victor Ustinov, Anton Egorov, Saiyi Han, Si-Cong Tian and Dieter Bimberg
Photonics 2023, 10(6), 660; https://doi.org/10.3390/photonics10060660 - 07 Jun 2023
Cited by 2 | Viewed by 1303
Abstract
A detailed experimental analysis of the impact of device topology on the performance of 1550 nm VCSELs with an active region based on thin InGaAs/InAlGaAs quantum wells and a composite InAlGaAs buried tunnel junction is presented. The high-speed performance of the lasers with [...] Read more.
A detailed experimental analysis of the impact of device topology on the performance of 1550 nm VCSELs with an active region based on thin InGaAs/InAlGaAs quantum wells and a composite InAlGaAs buried tunnel junction is presented. The high-speed performance of the lasers with L-type device topology (with the largest double-mesa sizes) is mainly limited by electrical parasitics showing noticeable damping of the relaxation oscillations. For the S-type device topology (with the smallest double-mesa sizes), the decrease in the parasitic capacitance of the reverse-biased p+n-junction region outside the buried tunnel junction region allowed to raise the parasitic cutoff frequency up to 13–14 GHz. The key mechanism limiting the high-speed performance of such devices is thus the damping of the relaxation oscillations. VCSELs with S-type device topology demonstrate more than 13 GHz modulation bandwidth and up to 37 Gbps nonreturn-to-zero data transmission under back-to-back conditions at 20 °C. Full article
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9 pages, 1822 KiB  
Article
Long-Cavity M-Plane GaN-Based Vertical-Cavity Surface-Emitting Lasers with a Topside Monolithic Curved Mirror
by Nathan C. Palmquist, Ryan Anderson, Jared A. Kearns, Joonho Back, Emily Trageser, Stephen Gee, Steven P. Denbaars and Shuji Nakamura
Photonics 2023, 10(6), 646; https://doi.org/10.3390/photonics10060646 - 03 Jun 2023
Cited by 2 | Viewed by 1949
Abstract
We report long-cavity (60.5 λ) GaN-based vertical-cavity surface-emitting lasers with a topside monolithic GaN concave mirror, a buried tunnel junction current aperture, and a bottomside nanoporous GaN distributed Bragg reflector. Under pulsed operation, a VCSEL with a 9 µm aperture had a threshold [...] Read more.
We report long-cavity (60.5 λ) GaN-based vertical-cavity surface-emitting lasers with a topside monolithic GaN concave mirror, a buried tunnel junction current aperture, and a bottomside nanoporous GaN distributed Bragg reflector. Under pulsed operation, a VCSEL with a 9 µm aperture had a threshold current density of 6.6 kA/cm2, a differential efficiency of 0.7%, and a maximum output power of 290 µW for a lasing mode at 411 nm and a divergence angle of 8.4°. Under CW operation, the threshold current density increased to 7.3 kA/cm2, the differential efficiency decreased to 0.4%, and a peak output power of 130 µW was reached at a current density of 23 kA/cm2. Full article
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11 pages, 3700 KiB  
Article
Quantum Dot Lasers Directly Grown on 300 mm Si Wafers: Planar and In-Pocket
by Kaiyin Feng, Chen Shang, Eamonn Hughes, Andrew Clark, Rosalyn Koscica, Peter Ludewig, David Harame and John Bowers
Photonics 2023, 10(5), 534; https://doi.org/10.3390/photonics10050534 - 06 May 2023
Cited by 2 | Viewed by 3196
Abstract
We report for the first time the direct growth of quantum dot (QD) lasers with electrical pumping on 300 mm Si wafers on both a planar template and in-pocket template for in-plane photonic integration. O-band lasers with five QD layers were grown with [...] Read more.
We report for the first time the direct growth of quantum dot (QD) lasers with electrical pumping on 300 mm Si wafers on both a planar template and in-pocket template for in-plane photonic integration. O-band lasers with five QD layers were grown with molecular beam epitaxy (MBE) in a 300 mm reactor and then fabricated into standard Fabry–Perot ridge waveguide cavities. Edge-emitting lasers are demonstrated with high yield and reliable results ready for commercialization and scaled production, and efforts to make monolithically integrated lasing cavities grown on silicon-on-insulator (SOI) wafers vertically aligned and coupled to SiN waveguides on the same chip show the potential for 300 mm-scale Si photonic integration with in-pocket direct MBE growth. Full article
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12 pages, 5623 KiB  
Communication
Surface-Emitting Lasers with Surface Metastructures
by Anjin Liu, Jing Zhang, Chenxi Hao, Minglu Wang and Wanhua Zheng
Photonics 2023, 10(5), 509; https://doi.org/10.3390/photonics10050509 - 27 Apr 2023
Cited by 2 | Viewed by 1257
Abstract
Vertical-cavity surface-emitting lasers (VCSELs) have been widely used in consumer electronics, light detection and ranging, optical interconnects, atomic sensors, and so on. In this paper, a VCSEL with the surface metastructure like one-dimensional high-contrast grating (HCG), based on the HCG-DBR vertical cavity, was [...] Read more.
Vertical-cavity surface-emitting lasers (VCSELs) have been widely used in consumer electronics, light detection and ranging, optical interconnects, atomic sensors, and so on. In this paper, a VCSEL with the surface metastructure like one-dimensional high-contrast grating (HCG), based on the HCG-DBR vertical cavity, was first designed and fabricated. The polarization characteristic of the HCG-VCSEL were experimentally studied. The p-doped top 4-pair DBR for the current spreading and the direction shift between the HCG and the elliptical oxide aperture may result in a low orthogonal polarization suppression ratio in the HCG-VCSEL. Then, the Bloch surface wave surface-emitting laser (BSW-SEL), based on the HCG-DBR metastructure, is proposed for single-mode, high-efficiency, and high-power output with a low divergence angle. The mode field and the far field profile of the BSW-SEL are calculated for verification. The surface-emitting lasers with surface metastructures are useful for the sensing applications and optical interconnects. Full article
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10 pages, 7976 KiB  
Communication
All-Monolithically Integrated Self-Scanning Addressable VCSEL Array for 3D Sensing
by Takashi Kondo, Junichiro Hayakawa, Daisuke Iguchi, Tomoaki Sakita, Takafumi Higuchi, Kei Takeyama, Seiji Ohno, Michiaki Murata and Hiroyuki Usami
Photonics 2023, 10(3), 304; https://doi.org/10.3390/photonics10030304 - 13 Mar 2023
Cited by 3 | Viewed by 2192
Abstract
We propose an all-monolithically integrated self-scanning addressable vertical-cavity surface-emitting laser array for time-of-flight measurement. Some advantages of addressable VCSELs for ToF measurement applications include large reductions in power consumption, heat generation, multi-pass noise, and flare noise. In this paper, we discuss the characteristics [...] Read more.
We propose an all-monolithically integrated self-scanning addressable vertical-cavity surface-emitting laser array for time-of-flight measurement. Some advantages of addressable VCSELs for ToF measurement applications include large reductions in power consumption, heat generation, multi-pass noise, and flare noise. In this paper, we discuss the characteristics of the proposed self-scanning addressable VCSEL array. All layers in the epilayer structure of the proposed VCSEL array were formed at once by metal-organic chemical vapor deposition. The device consists of an (Al)GaAs-based thyristor and a conventional top-emitting 940-nm oxide-confined VCSEL on an n-type GaAs substrate. The array contained 12 blocks (4 × 3) that have more than 40 emitters each. The device required only four signals from a field-programmable gate array to select the emitting blocks and one emission signal from a conventional VCSEL driver, even for arrays containing hundreds of blocks. The proposed module is capable of one-block sequential emission, parallel emission from several blocks, and emission from all blocks. The rise and fall times of the fabricated VCSEL array were observed to be 200 and 400 ps, respectively, for each emission mode. The influence of flare noise from an obstacle in front of the camera was dramatically reduced by avoiding emission to the obstacle. Full article
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11 pages, 4158 KiB  
Communication
Half-Ring Microlasers Based on InGaAs Quantum Well-Dots with High Material Gain
by Fedor Zubov, Eduard Moiseev, Mikhail Maximov, Alexander Vorobyev, Alexey Mozharov, Yuri Shernyakov, Nikolay Kalyuzhnyy, Sergey Mintairov, Marina Kulagina, Vladimir Dubrovskii, Natalia Kryzhanovskaya and Alexey Zhukov
Photonics 2023, 10(3), 290; https://doi.org/10.3390/photonics10030290 - 10 Mar 2023
Cited by 1 | Viewed by 1148
Abstract
We report on half-ring lasers that are 100–200 µm in diameter and are fabricated by cleaving the initial full rings into halves. Characteristics of the half-ring and half-disk lasers fabricated from the same wafer are compared. The active area of the microlasers is [...] Read more.
We report on half-ring lasers that are 100–200 µm in diameter and are fabricated by cleaving the initial full rings into halves. Characteristics of the half-ring and half-disk lasers fabricated from the same wafer are compared. The active area of the microlasers is based on the quantum heterostructures of mixed (0D/2D) dimensionality, referred to as quantum well-dots with very high material gain. Half-ring lasers show directional light emission and single-mode lasing near the threshold. A maximal continuous-wave output power of 76 mW is achieved for a half-ring that is 200 µm in diameter. Half-rings demonstrate better wall-plug efficiency as compared to half-disks. Lasing in pulse mode is observed up to 140 °C, the characteristic temperature is 100–125 K, depending on the half-ring size. P-side down bonding onto Si-board significantly improves power and temperature characteristics. In CW mode, lasing is maintained up to 97 °C, limited by active-area overheating. Full article
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12 pages, 2812 KiB  
Communication
Digital Non-Linear Transmitter Equalization for PAM-N-Based VCSEL Links Enabling Robust Data Transmission of 100 Gbit/s and Beyond
by Urs Hecht, Nikolay Ledentsov, Jr., Helia Ordouei, Patrick Kurth, Philipp Scholz, Nikolay Ledentsov and Friedel Gerfers
Photonics 2023, 10(3), 280; https://doi.org/10.3390/photonics10030280 - 07 Mar 2023
Cited by 3 | Viewed by 1665
Abstract
This paper demonstrates why VCSEL-based transmitter systems are not able to capitalize on higher-order PAM modulation formats (such as PAM-4) to push the link data rate towards 100 Gbit/s with BER of better than 105. First, the non-linear and biasing-dependent [...] Read more.
This paper demonstrates why VCSEL-based transmitter systems are not able to capitalize on higher-order PAM modulation formats (such as PAM-4) to push the link data rate towards 100 Gbit/s with BER of better than 105. First, the non-linear and biasing-dependent VCSEL behavior is analyzed in great detail to prove why state-of-the-art VCSELs with linear equalization are not able to reach these bandwidth targets. Consequently, based on an enhanced VCSEL model, a digital non-linear transmit equalizer is proposed to overcome voltage-dependent relaxation frequency shifts as well as data-dependent VCSEL bandwidth variations. The proposed digital non-linear equalizer is compared with a standard linear FFE structure using PAM-4 transmission experiments of 100 Gbit/s and beyond. This way, the proposed non-linear equalizer reveals a BER improvement of more than 30-fold compared to a linear FFE at a data rate of 80 Gbit/s. Finally, at 112 Gbit/s PAM-4 the non-linear equalizer was successfully demonstrated at a BER of 1.5·107. Full article
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11 pages, 1598 KiB  
Communication
Two-State Lasing in Microdisk Laser Diodes with Quantum Dot Active Region
by Ivan Makhov, Konstantin Ivanov, Eduard Moiseev, Anna Dragunova, Nikita Fominykh, Yuri Shernyakov, Mikhail Maximov, Natalia Kryzhanovskaya and Alexey Zhukov
Photonics 2023, 10(3), 235; https://doi.org/10.3390/photonics10030235 - 21 Feb 2023
Cited by 4 | Viewed by 1421
Abstract
The two-state lasing phenomenon, which manifests itself in simultaneous laser emission through several optical transitions of quantum dots, is studied in microdisk diode lasers with different cavity diameters. The active region represents a multiply stacked array of self-organized InAs/InGaAs/GaAs quantum dots emitting in [...] Read more.
The two-state lasing phenomenon, which manifests itself in simultaneous laser emission through several optical transitions of quantum dots, is studied in microdisk diode lasers with different cavity diameters. The active region represents a multiply stacked array of self-organized InAs/InGaAs/GaAs quantum dots emitting in the wavelength range of 1.1–1.3 µm. Two-state lasing, which involves the ground-state and the first excited-state optical transitions, is observed in microdisks with cavity diameters of 20 to 28 µm, whereas two-state lasing via the first and the second excited-state optical transitions is observed in 9 µm microdisks. The threshold currents for one-state and two-state lasing are investigated as functions of the microdisk diameter. Optical loss in the microdisk lasers is evaluated by comparing the two-state lasing behavior of the microdisks with that of edge-emitting stripe lasers made of the same epitaxial wafer. Full article
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22 pages, 45170 KiB  
Article
Design of High Peak Power Pulsed Laser Diode Driver
by Ching-Yao Liu, Chih-Chiang Wu, Li-Chuan Tang, Wei-Hua Chieng, Edward-Yi Chang, Chun-Yen Peng and Hao-Chung Kuo
Photonics 2022, 9(9), 652; https://doi.org/10.3390/photonics9090652 - 14 Sep 2022
Cited by 2 | Viewed by 6561
Abstract
This paper attempts to describe a laser diode driver circuit using the depletion mode gallium nitride high electron mobility transistor (D-mode GaN HEMT) to generate nanosecond pulses at a repetition rate up to 10 MHz from the vertical-cavity surface-emitting laser (VCSEL). The feature [...] Read more.
This paper attempts to describe a laser diode driver circuit using the depletion mode gallium nitride high electron mobility transistor (D-mode GaN HEMT) to generate nanosecond pulses at a repetition rate up to 10 MHz from the vertical-cavity surface-emitting laser (VCSEL). The feature of this driver circuit is a large instantaneous laser power output designed in the most efficient way. The design specifications include a pulse duration between 10 ns and 100 ns and a peak power up to above 100 W. The pulsed laser diode driver uses the D-mode GaN HEMT, which has very small Coss difference between turn-on and turn-off states. The analysis is according to a laser diode model that is adjusted to match the VCSEL, made in National Yang Ming Chiao Tung University (NYCU). A design guide is summarized from the derivations and analysis of the proposed laser diode driver. According to the design guide, we selected the capacitor, resistor, and diode components to achieve 10 ns to 100 ns pulse duration for laser lighting. The experiment demonstrated that the maximum power-to-light efficiency can be as high as 86% and the maximum peak power can be 150 W, which matches the specifications of certain applications such as light detection and ranging (LiDAR). Full article
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Review

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15 pages, 5576 KiB  
Review
GaN-Based VCSELs with A Monolithic Curved Mirror: Challenges and Prospects
by Tatsushi Hamaguchi
Photonics 2023, 10(4), 470; https://doi.org/10.3390/photonics10040470 - 20 Apr 2023
Cited by 5 | Viewed by 2513
Abstract
In this paper, we introduce how gallium nitride-based (GaN-based) VCSELs with curved mirrors have evolved. The discussion starts with reviewing the fundamentals of VCSELs and GaN-based materials and then introducing the curved-mirror cavity’s principle and history and the latest research where the structure [...] Read more.
In this paper, we introduce how gallium nitride-based (GaN-based) VCSELs with curved mirrors have evolved. The discussion starts with reviewing the fundamentals of VCSELs and GaN-based materials and then introducing the curved-mirror cavity’s principle and history and the latest research where the structure is applied to GaN-based materials to form VCSELs. We prepared these parts so that readers understand how VCSELs with this cavity work and provide excellent characteristics such as efficiency, life, stabilized mode behavior, etc. Finally, we discussed the challenges and prospects of these devices by touching on their potential applications. Full article
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17 pages, 5386 KiB  
Review
Progress in Short Wavelength Energy-Efficient High-Speed Vertical-Cavity Surface-Emitting Lasers for Data Communication
by Si-Cong Tian, Mansoor Ahamed and Dieter Bimberg
Photonics 2023, 10(4), 410; https://doi.org/10.3390/photonics10040410 - 06 Apr 2023
Cited by 5 | Viewed by 1930
Abstract
The current progress of energy-efficient high-speed VCSELs based on GaAs substrates is presented. Novel approaches for the design of VCSELs are presented, potentially leading to larger bandwidth bit rates and lower power consumption. The first approach is based on the optimization of the [...] Read more.
The current progress of energy-efficient high-speed VCSELs based on GaAs substrates is presented. Novel approaches for the design of VCSELs are presented, potentially leading to larger bandwidth bit rates and lower power consumption. The first approach is based on the optimization of the VCSEL photon lifetime. The second one introduces a novel design based on oxidizing the apertures from multiple etched holes of varying geometries. These designs are also essential for improving the energy efficiency of future modules by optimizing the match of the electronic driver and the photonic device. Full article
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22 pages, 4225 KiB  
Review
Long-Wavelength VCSELs: Status and Prospects
by Andrey Babichev, Sergey Blokhin, Evgenii Kolodeznyi, Leonid Karachinsky, Innokenty Novikov, Anton Egorov, Si-Cong Tian and Dieter Bimberg
Photonics 2023, 10(3), 268; https://doi.org/10.3390/photonics10030268 - 03 Mar 2023
Cited by 7 | Viewed by 4777
Abstract
Single-mode long-wavelength (LW) vertical-cavity surface-emitting lasers (VCSELs) present an inexpensive alternative to DFB-lasers for data communication in next-generation giga data centers, where optical links with large transmission distances are required. Narrow wavelength-division multiplexing systems demand large bit rates and single longitudinal and transverse [...] Read more.
Single-mode long-wavelength (LW) vertical-cavity surface-emitting lasers (VCSELs) present an inexpensive alternative to DFB-lasers for data communication in next-generation giga data centers, where optical links with large transmission distances are required. Narrow wavelength-division multiplexing systems demand large bit rates and single longitudinal and transverse modes. Spatial division multiplexing transmission through multicore fibers using LW VCSELs is enabling still larger-scale data center networks. This review discusses the requirements for achieving high-speed modulation, as well as the state-of-the-art. The hybrid short-cavity concept allows for the realization of f3dB frequencies of 17 GHz and 22 GHz for 1300 nm and 1550 nm range VCSELs, respectively. Wafer-fusion (WF) concepts allow the realization of long-time reliable LW VCSELs with a record single-mode output power of more than 6 mW, 13 GHz 3 dB cut-off frequency, and data rates of 37 Gbit/s for non-return-to-zero (NRZ) modulation at 1550 nm. Full article
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