A5037979283- Semiconductor Lasers and Optical Devices
- Photonic and Optical Devices
- Semiconductor Quantum Structures and Devices
- Optical Network Technologies
- Molecular Junctions and Nanostructures
- Optical Wireless Communication Technologies
- Semiconductor materials and devices
- Advanced machining processes and optimization
- Crystallography and molecular interactions
- Gamma-ray bursts and supernovae
- X-ray Diffraction in Crystallography
- Advanced Photonic Communication Systems
- Crystallization and Solubility Studies
- Advanced Fiber Laser Technologies
- Astrophysical Phenomena and Observations
- Engineering Technology and Methodologies
- Advanced Polymer Synthesis and Characterization
- Ultrasonics and Acoustic Wave Propagation
- GaN-based semiconductor devices and materials
- Solid State Laser Technologies
- Advancements in Semiconductor Devices and Circuit Design
- Laser Material Processing Techniques
- Advancements in PLL and VCO Technologies
- Semiconductor materials and interfaces
- Synthesis and properties of polymers
National Taiwan University
2021-2024
Feng Chia University
2020-2021
Institute of High Energy Physics
2020
Chinese Academy of Sciences
1996-2020
Northeastern University
2008
Jiangsu University of Science and Technology
2002
National Laboratory for Superconductivity
1996
K Lab (United States)
1991-1994
Lockheed Martin (United States)
1990-1991
Lockheed Martin (Canada)
1991
Vertical-cavity surface-emitting lasers (VCSELs) have made remarkable progress, are being used across a wide range of consumer electronic applications, and particularly received much attention from the telecom datacom industries. However, several constraints thus currently tackled to improve device characteristics modulation formats meet various demanding requirements future 800 GbE 1.6 TbE Ethernet standards. This manuscript discusses key considerations in designs optimizations. Finally, we...
This research successfully developed an independent Ge-based VCSEL epitaxy and fabrication technology route, which set the stage for integrating AlGaAs-based semiconductor devices on bulk Ge substrates. is second successful reported worldwide first with key details disclosed, including substrate specification, transition layer structure composition, process. Compared GaAs counterparts, after optimization, wafer has a 40% lower surface root-mean-square roughness 72% average bow-warp. After...
This letter presents a single-mode vertical-cavity surface-emitting laser (VCSEL) using novel ring-shaped self-aligned recessed metal (SARM) mode filter on the emitting window as means of transverse control. The SARM structure acts spatial to suppress higher-order modes through selective recessed-etching top mirror and deposition p-type contact metals for cavity tuning blocking modes. could be potentially high-yield alternative technique mass production VCSELs, demonstrating emission with...
We report on a high-performance oxide-confined 850-nm vertical-cavity surface-emitting laser (VCSEL) believed to have the highest modulation bandwidth at low bias currents for datacenter applications. This article has extensively discussed device's characteristics, including static performance, optical spectra, small-signal response, relative intensity noise (RIN), and large-signal performance. The VCSEL with an oxide aperture of 4 μm delivers 3.7 mW power, spectral width, below −150 dB/Hz...
In this Letter, we present a comprehensive analysis of the high-speed performance 940 nm oxide-confined AlGaAs vertical-cavity surface-emitting lasers (VCSELs) grown on Ge substrates. Our demonstration reveals pronounced superiority Ge-based VCSELs in terms thermal stability. The presented Ge-VCSEL has maximum modulation bandwidth 16.1 GHz and successfully realizes 25 Gb/s NRZ transmission at 85 ∘ C. experimental results underscore significance potential Ge-VCSELs for applications requiring...
The detuning between the spectral positions of gain peaks and cavity resonances greatly influences elevated temperature performances vertical-cavity surface-emitting lasers (VCSELs). Therefore, design optimization gain–cavity in VCSELs have long been piquing researchers' interest. This work presents an 850-nm dual-mode-VCSEL meticulously designed with qualified higher-temperature mind. Bringing enhanced functionalities over extended operating temperatures, delivering 3-dB bandwidths 27.5 GHz...
In this investigation, we propose and demonstrate an integrated vertical-cavity surface-emitting laser (VCSEL) blue light emitting diode (LED) based visible communication (VLC) system by using the decode-and-forward (DF) relay scheme indoors. The 682 nm VCSEL can reach 3 Gbit/s on-off keying (OOK) modulation rate for 4 m free space transmission applying 1.25 GHz bandwidth PIN photodiode (PD). Then, VLCVCSEL signal connects to multiple LEDs broadcasting VLCLED traffic in parallel. Therefore,...
High quality 940 nm Al x Ga 1-x As n-type distributed Bragg reflectors (DBRs) were successfully monolithically grown on off-cut Ge (100) substrates. The Ge-DBRs have reflectivity spectra comparable to those conventional bulk GaAs substrates and smooth morphology reasonable periodicity. These results strongly support VCSEL growth fabrication more scalable for larger scale production of AlGaAs-based VCSELs.
This article presents an all-epitaxy approach to reduce the root mean square spectral width (Δ λ R M S ) of 850 nm oxide-confined vertical cavity surface-emitting lasers (VCSELs) with a large aperture 7 µm through strategic optimization oxide guiding layer within epitaxy structure. At 75°C, VCSEL demonstrates Δ ∼0.3 at bias current 7.5 mA. Furthermore, achieves successful transmission 26.5625 Gbaud PAM-4 modulation over short-reach (SR) OM4 fiber link while maintaining TDECQ budget below 4.5...
Mushroom structure vertical cavity surface emitting lasers with a 0.6- mu m GaAs active layer sandwiched by two Al/sub 0.6/Ga/sub 0.4/As-Al/sub 0.08/Ga/sub 0.92/As multilayers as top and bottom mirrors are discussed. The exhibit 15-mA pulses threshold current at 880 nm. Single longitudinal single transverse mode operation was achieved on 5- m-diameter region of levels near 2*l/sub th/. light output above linearly polarized polarization ratio 25:1.< <ETX...
Room-temperature continuous-wave (cw) lasing operation with a threshold current (Ith) of 3 mA and pulsed Ith as low 1.5 were achieved in mushroom structure surface- emitting lasers utilizing 300 Å GaAs single quantum well an active layer AlAs/Al0.1Ga0.9As multilayer the top bottom distributed Bragg reflectors. A series resistance 250 Ω was obtained on devices 8×8 μm2 region using selective zinc diffusion. differential efficiency 12%–20% maximum cw light output power exceeding 1 mW achieved....
The velocities of longitudinal and transverse waves for aluminum alloy 2024-T62 shocked by a high-power Nd: Glass laser are investigated ultrasonics method. results show that the velocity wave measured after laser-shock processing increases at center decreases edge laser-shocked area (LSA). maximum relative increase is 28% decrease up to 10%, when compared with before was processing. any position within LSA, being 13%. LSA larger than center.
To increase the data capacity of a light-emitting diode (LED) based visible light communication (VLC) transmission, polarization-division-multiplexing (PMD) green (G)- and blue (B)- light-based transmitter (Tx) module is demonstrated here. It was that we can achieve 1200 1120 Mbps VLC capacities on dual-polarized G- B-LED wave after 3 4 m free-space link lengths, respectively, at exceedingly low illuminance. Based presented system, paired G-LEDs or B-LEDs with dual-polarization also be...
A surface emitting laser diode (SELD) with two distributed Bragg reflectors (DBR) and semiconductor multilayer airbridge-supported top mirror is fabricated. low threshold current of 1.5 mA achieved under room temperature CW operation. The spectrum shows a strong peak at 891 nm FWHM 10 Å. With light emission from the reflector instead back side substrate, arrays are easily formed this novel structure.
We report on the observation of accreting pulsar GRO J1008-57 performed by Insight-HXMT at peak source's 2017 outburst. Pulsations are detected with a spin period 93.283(1) s. The pulse profile shows double peaks soft X-rays, and only one above 20 keV. spectrum is well described phenomenological models X-ray pulsars. A cyclotron resonant scattering feature very high statistical significance centroid energy $E_{\rm cyc}=90.32_{-0.28}^{+0.32}$ keV, for reference continuum line models, HIGHECUT...
This work successfully developed an independent Ge-VCSEL epitaxy and fabrication technology route. is the second successful reported worldwide, first with key details disclosed, including Ge substrate specification, transition layer structure composition, process etc. Compared GaAs counterparts, after optimization, wafer has a 40% lower surface root-mean square roughness 72% average bow-warp. Additionally, 10% threshold current density 19% higher maximum slope efficiency than GaAs-VCSEL.
This achievement marks a major milestone, establishing dedicated pathway for epitaxy and fabrication of high-speed Ge-VCSELs. technology offers extensive insights into epitaxial processes, advancing the field VCSEL development.
Micro light-emitting diodes (µLEDs), crucial for advanced displays and communication systems, face efficiency challenges due to sidewall defects. This study investigates the impact of various passivation layers, including SiO 2 , Al O 3 HfO on AlGaInP-based 620 nm red µLEDs. We fabricated devices with two mesa sizes demonstrated that atomic layer deposition (ALD) passivation, especially significantly enhances performance. shows improvement in external quantum (EQE) by up 57.9% a 13 × 20 µm...