Semipolar InGaN-based superluminescent diodes for solid-state lighting and visible light communications
Type
Conference PaperAuthors
Shen, Chao
Ng, Tien Khee
Lee, Changmin
Leonard, John T.
Nakamura, Shuji
Speck, James S.
Denbaars, Steven P.
Alyamani, Ahmed Y.
El-Desouki, Munir M.
Ooi, Boon S.
KAUST Department
Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) DivisionElectrical Engineering Program
KAUST Grant Number
BAS/1/1614-01-01Date
2017-02-16Permanent link to this record
http://hdl.handle.net/10754/623329Metadata
Show full item recordAbstract
III-nitride light emitters, such as light-emitting diodes (LEDs) and laser diodes (LDs), have been demonstrated and studied for solid-state lighting (SSL) and visible-light communication (VLC) applications. However, for III-nitride LEDbased SSL-VLC system, its efficiency is limited by theCitation
Shen C, Ng TK, Lee C, Leonard JT, Nakamura S, et al. (2017) Semipolar InGaN-based superluminescent diodes for solid-state lighting and visible light communications . Gallium Nitride Materials and Devices XII. Available: http://dx.doi.org/10.1117/12.2251144.Sponsors
The authors acknowledge the financial support from King Abdulaziz City for Science and Technology (KACST) Grant No. KACST TIC R2-FP-008, and KACST-KAUST-UCSB Solid-State Lighting Program. This work is partially supported by King Abdullah University of Science and Technology (KAUST) baseline funding (BAS/1/1614-01-01).Publisher
SPIE-Intl Soc Optical EngConference/Event name
Gallium Nitride Materials and Devices XIIScopus Count
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Fabrication and Characterization of GaN-Based Superluminescent Diode for Solid-State Lighting and Visible Light Communication(2020-04) [Dissertation]
Advisor: Ooi, Boon S.
Committee members: Ohkawa, Kazuhiro; Mohammed, Omar F.; Zhao, HongPingTo date, group-III-nitride has undergone continuous improvements to provide a broader range of industrial applications, such as solid-state lighting (SSL), visible light communications (VLC), and light projection. Recently, VLC has attained substantial attention in the field of wireless communication because it offers ~ 370 THz of bandwidth of unregulated visible spectrum, which makes it a critical factor in the evolution of the 5G networks and beyond. GaN-based light-emitting diode (LED) and laser diode (LD) have become increasingly appealing in energy-sufficient SSL replacing conventional light sources. However, III- nitride LEDs suffer from efficiency-droop in their external quantum efficiency associated with high current densities, and their modulation bandwidth is limited to 10 ~ 100 MHz. Although LDs have shown gigabit-modulation bandwidth, unfavorable artifacts, such as speckles are observed, which may raise a concern about eye safety. This dissertation is devoted to the fabrication and electrical and optical characterization of a new class of III-nitride light-emitter known as superluminescent diode (SLD). SLD works in an amplified spontaneous emission (ASE) regime, and it combines several advantages from both LD and LED, such as droop-free, speckle-free, low-spatial coherence, broader emission, high-optical power, and directional beam. Here, SLDs were fabricated by a focused ion beam by tilting the front facet of the waveguide to suppress the lasing mode. They showed a high-power of 474 mW on c-plane GaN-substrate with a large spectral bandwidth of 6.5 nm at an optical power of 105 mW. To generate SLD- based white light, a YAG-phosphor-plate was integrated, and a CRI of 85.1 and CCT of 3392 K were measured. For the VLC link, SLD showed record high-data rates of 1.45 Gbps and 3.4 Gbps by OOK and DMT modulation schemes, respectively. Additionally, a widely single- and dual-wavelength tunability were designed using SLD-based external cavity (SLD-EC) configuration for a tunable blue laser source. These results underscore the practicality of c-plane SLDs in realizing high-power, high data rate, speckle-free, and droop-free SSL-VLC apparatus. Additionally, the SLD-EC configuration allows a wide range of applications, including biomedical applications, optical communication, and high-resolution spectroscopy.
