Visible light metasurfaces based on gallium nitride high contrast gratings

2016 ◽  
Vol 367 ◽  
pp. 144-148 ◽  
Author(s):  
Zhenhai Wang ◽  
Shumin He ◽  
Qifa Liu ◽  
Wei Wang
Keyword(s):  
Gallium Nitride ◽  
Visible Light ◽  
High Contrast

Site Selective Magneto-Optical Studies of Eu ions in Gallium Nitride

2011 ◽  
Vol 1342 ◽  
Author(s):  
Nathaniel Woodward ◽  
Atsushi Nishikawa ◽  
Yasufumi Fujiwara ◽  
Volkmar Dierolf
Keyword(s):  
Gallium Nitride ◽  
Magnetic Fields ◽  
Visible Light ◽  
Resonant Excitation ◽  
Optical Studies ◽  
G Value ◽  
Site Selective

ABSTRACTWe report site-selective studies of the Zeeman splittings that are observed for magnetic fields up to 6.6T for different Eu incorporation sites in GaN. Utilizing resonant excitation with visible light, we are able to distinguish the site and find for one center (Eu1) a splitting into five components as expected for C3v symmetry. The corresponding g-values are 1.66 and 1.90. The two lines of another center Eu2 each split into two levels corresponding to g-values of 1.9 and 2.84. Most surprisingly a third center, for which only one line is clearly identified, a g-value of 6.16 is found which is larger than can be explained for a 7F2 purely ionic Eu state.

scholarly journals Narrow Linewidth Distributed Bragg Reflectors Based on InGaN/GaN Laser

Micromachines ◽  
2019 ◽  
Vol 10 (8) ◽  
pp. 529 ◽  
Author(s):  
Xie ◽  
Li ◽  
Liao ◽  
Deng ◽  
Wang ◽  
...  
Keyword(s):  
Gallium Nitride ◽  
Visible Light ◽  
Communication Systems ◽  
Fdtd Method ◽  
Visible Light Communication ◽  
Bragg Reflector ◽  
Duty Ratio ◽  
Light Sources ◽  
Distributed Bragg Reflector ◽  
Dbr Lasers

A variety of emerging technologies, such as visible light communication systems, require narrow linewidths and easy-to-integrate light sources. Such a requirement could be potentially fulfilled with the distributed Bragg reflector (DBR) lasers, which are also promising for the monolithical integration with other optical components. The InGaN/GaN-based surface etched DBR is designed and optimized using the finite-difference-time-domain (FDTD) method to obtain very narrow-band reflectors that can serve as a wavelength filter. The results reveal that the ultimate reflectivity depends on the grating period and duty ratio of the DBR. Based on the design, the DBR lasers with various duty ratios are fabricated, specifically, the 19th, 13th and 3rd order DBR grating with duty ratio set as 50%/75%/95%. The minimum linewidth could be achieved at 0.45 nm from the 19th order grating with a 75% duty ratio. For comparison, the Fabry–Pérot (F–P) based on the same indium gallium nitride/gallium nitride (InGaN/GaN) epitaxial wafer are fabricated. The full width at half maximum (FWHM) of the DBR laser shrank by 65% compared to that of the conventional F–P laser, which might be helpful in the application of the visible light communication system.

scholarly journals A review of gallium nitride LEDs for multi-gigabit-per-second visible light data communications

2017 ◽  
Vol 32 (2) ◽  
pp. 023001 ◽  
Author(s):  
Sujan Rajbhandari ◽  
Jonathan J D McKendry ◽  
Johannes Herrnsdorf ◽  
Hyunchae Chun ◽  
Grahame Faulkner ◽  
...  
Keyword(s):  
Gallium Nitride ◽  
Visible Light ◽  
Data Communications

scholarly journals Carborane photochromism: A fatigue resistant carborane switch

2021 ◽  
Author(s):  
Chong Li ◽  
Matthew Phillip Aldred ◽  
Rachel Abigail Harder ◽  
Chen Ying ◽  
Dimitrii S. Yufit ◽  
...  
Keyword(s):  
Visible Light ◽  
Fatigue Resistance ◽  
High Contrast ◽  
Colour Changes ◽  
Visual Colour

A dithienylethene molecule involving carborane clusters shows remarkable fatigue resistance and high contrast visual colour changes when irradiated with alternating ultraviolet and visible light. The fluorescence of this assembly can...

scholarly journals Photo-Switchable Aggregation-Induced Emission of Bisthienylethene-Dipyrimido[2,1-b][1,3]benzothiazole Triad

Molecules ◽  
2021 ◽  
Vol 26 (17) ◽  
pp. 5382
Author(s):  
Shan-Shan Gong ◽  
Chun-Hong Zheng ◽  
Zhen-Zhen Chen ◽  
Dong-Zhao Yang ◽  
Mei Chi ◽  
...  
Keyword(s):  
Solid State ◽  
Visible Light ◽  
Visible Light Irradiation ◽  
Potential Application ◽  
Optical Memory ◽  
Light Irradiation ◽  
Pmma Film ◽  
High Contrast ◽  
Photochromic Properties ◽  
Non Destructive

A bisthienylethene-dipyrimido[2,1-b][1,3]benzothiazole (BTE-2PBT) triad has been designed and synthesized based on our recent discovery of PBTs as atypical propeller-shaped novel AIEgens. The triad not only maintains the photochromic properties of BTE moiety in solution, film, and solid state but also exhibits remarkable AIE properties. Moreover, the fluorescence of BTE-2PBT PMMA film could be modulated with high contrast by alternate UV and visible light irradiation. Photoerasing, rewriting, and non-destructive readout of fluorescent images on BTE-2PBT PMMA film well demonstrate its potential application as optical memory media.

Self-coherent camera: first results of a high-contrast imaging bench in visible light

2010 ◽  
Author(s):  
Marion Mas ◽  
Pierre Baudoz ◽  
Gerard Rousset ◽  
Raphaël Galicher ◽  
Jacques Baudrand
Keyword(s):  
Visible Light ◽  
High Contrast ◽  
Contrast Imaging ◽  
High Contrast Imaging ◽  
First Results

scholarly journals Porous AlGaN-Based Ultraviolet Distributed Bragg Reflectors

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1487 ◽  
Author(s):  
Peter Griffin ◽  
Tongtong Zhu ◽  
Rachel Oliver
Keyword(s):  
Gallium Nitride ◽  
Visible Light ◽  
Electrochemical Etching ◽  
High Density ◽  
Etching Process ◽  
Bragg Reflectors ◽  
Distributed Bragg Reflectors ◽  
Material Growth ◽  
Low Efficiency ◽  
Uv Leds

Utilising dislocation-related vertical etching channels in gallium nitride, we have previously demonstrated a simple electrochemical etching (ECE) process that can create layered porous GaN structures to form distributed Bragg reflectors for visible light at wafer scale. Here, we apply the same ECE process to realise AlGaN-based ultraviolet distributed Bragg reflectors (DBRs). These are of interest because they could provide a pathway to non-absorbing UV reflectors to enhance the performance of UV LEDs, which currently have extremely low efficiency. We have demonstrated porous AlGaN-based UV DBRs with a peak reflectance of 89% at 324 nm. The uniformity of these devices is currently low, as the as-grown material has a high density of V-pits and these alter the etching process. However, our results indicate that if the material growth is optimised, the ECE process will be useful for the fabrication of UV reflectors.

Electron-accepting carborane viologen and iron based-supramolecular polymers for electrochromism and enhanced photocatalytic hydrogen evolution

2020 ◽  
Vol 8 (46) ◽  
pp. 16326-16332
Author(s):  
Xiaodong Yang ◽  
Yueyan Zhang ◽  
Bingjie Zhang ◽  
Sikun Zhang ◽  
Xu Liu ◽  
...  
Keyword(s):  
Visible Light ◽  
Hydrogen Evolution ◽  
Optoelectronic Properties ◽  
Supramolecular Polymers ◽  
High Contrast ◽  
Photocatalytic Hydrogen Evolution ◽  
Visible Light Driven ◽  
Iron Based

CbV2+ and its FeSPs with good optoelectronic properties were used to fabricate a high contrast ECD and enhanced visible-light-driven HER.

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