wavelength band
Recently Published Documents


TOTAL DOCUMENTS

297
(FIVE YEARS 53)

H-INDEX

25
(FIVE YEARS 3)

2021 ◽  
Author(s):  
Siddharth Nambiar ◽  
Avijit Chatterjee ◽  
Shankar Kumar Selvaraja
Keyword(s):  

2021 ◽  
Author(s):  
Mohana University ◽  
Abdelrahman A. Elbadawi ◽  
K.H. Ibnaouf

Abstract This work demonstrates the spectral and amplified spontaneous emission (ASE) properties of a new chalcone laser dye material of 1-(4-methylsulfonyl phenyl)-3-(4-N, N dimethyl amino phenyl)-2-propen-1-one (MSPPP). The absorption, fluorescence, Stokes’ shift and quantum yield were obtained using different organic solvents. The energy band gap was calculated and compared with that of 3-[4-(dimethylamino) phenyl]-1-phenyl-(2E)-propen- 1-one (DAPPP). These include absorption, fluorescence, stokes shift, and amplified spontaneous emission (ASE). The absorption spectra of MSPPP showed a wavelength band in the range 403–427 nm, whereas the fluorescence spectra exhibited a band at 472–533 nm. ASE was observed under pump pulse laser excitation, and the wavelengths were attuned from 511 to 548 nm.


Materials ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 5952
Author(s):  
Fan Zhang ◽  
Qing Yang ◽  
Hao Bian ◽  
Shaokun Wang ◽  
Minjing Li ◽  
...  

Infrared (IR) microlens arrays (MLA) have attracted increasing interest for use in infrared micro-optical devices and systems. However, the beam homogenization of IR laser light is relatively difficult to achieve because most materials absorb strongly in the IR wavelength band. In this paper, we present a new method for the application of double-sided quasi-periodic chalcogenide glass (ChG) MLAs to infrared laser homogenization systems. These are non-regular arrays of closely spaced MLAs. The double-sided MLAs were successfully prepared on the ChG surface using a single-pulse femtosecond laser-assisted chemical etching technique and a precision glass molding technique. More than two million close-packed microlenses on the ChG surface were successfully fabricated within 200 min. By taking advantage of ChG’s good optical performance and transmittance (60%) in the infrared wavelength band (1~11μm), the homogenization of the IR beam was successfully achieved using the ChG quasi-periodic MLA.


Sensors ◽  
2021 ◽  
Vol 21 (16) ◽  
pp. 5624
Author(s):  
Jonghyun Lee ◽  
Youngrok Kim ◽  
Kihong Choi ◽  
Joonku Hahn ◽  
Sung-Wook Min ◽  
...  

We propose a compressive self-interference incoherent digital holography (SIDH) with a geometric phase metalens for section-wise holographic object reconstruction. We specify the details of the SIDH with a geometric phase metalens design that covers the visible wavelength band, analyze a spatial distortion problem in the SIDH and address a process of a compressive holographic section-wise reconstruction with analytic spatial calibration. The metalens allows us to realize a compressive SIDH system in the visible wavelength band using an image sensor with relatively low bandwidth. The operation of the proposed compressive SIDH is verified through numerical simulations.


2021 ◽  
Author(s):  
Shihao Li ◽  
Kejian Chen ◽  
Yeli Xu ◽  
Yan Chen

Abstract In this article, the effects of the rotation angle between upper and lower n-fold rotational symmetric nano-structures are studied. Various modes of circular dichroism (single wavelength band, dual-wavelength bands, and more than two wavelength bands) in the wavelength band from 3.3 to 5 µm are realized. Absorption up to 0.994 and absorptive circular dichroism up to 0.867 are observed. Meanwhile, sensitivity of circular dichroism to the rotation angle and reconfigure strategy for opposite responses has been discussed. Based on Born-Kuhn model, physical mechanism of mode’s switching is explained with charge distributions. The multi-mode chiroptical responses in mid-infrared band and the variety of design strategies have potential applications in the field of thermal remote sensing detection and tunable multi-band chiral devices.


2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Chaoyue Liu ◽  
Jingshu Guo ◽  
Laiwen Yu ◽  
Jiang Li ◽  
Ming Zhang ◽  
...  

AbstractTwo-dimensional materials (2DMs) have been used widely in constructing photodetectors (PDs) because of their advantages in flexible integration and ultrabroad operation wavelength range. Specifically, 2DM PDs on silicon have attracted much attention because silicon microelectronics and silicon photonics have been developed successfully for many applications. 2DM PDs meet the imperious demand of silicon photonics on low-cost, high-performance, and broadband photodetection. In this work, a review is given for the recent progresses of Si/2DM PDs working in the wavelength band from near-infrared to mid-infrared, which are attractive for many applications. The operation mechanisms and the device configurations are summarized in the first part. The waveguide-integrated PDs and the surface-illuminated PDs are then reviewed in details, respectively. The discussion and outlook for 2DM PDs on silicon are finally given.


2021 ◽  
Vol 11 (6) ◽  
pp. 2828
Author(s):  
Byoung-Seong Jeong

In this study, the optimal structure for obtaining high green color purity was investigated by modeling quantum dot (QD)–organic light-emitting diodes (OLED). It was found that even if the green quantum dot (G-QD) density in the G-QD layer was 30%, the full width at half maximum (FWHM) in the green wavelength band could be minimized to achieve a sharp emission spectrum, but it was difficult to completely block the blue light leakage with the G-QD layer alone. This blue light leakage problem was solved by stacking a green color filter (G-CF) layer on top of the G-QD layer. When G-CF thickness 5 μm was stacked, blue light leakage was blocked completely, and the FWHM of the emission spectrum in the green wavelength band was minimized, resulting in high green color purity. It is expected that the overall color gamut of QD-OLED can be improved by optimizing the device that shows such excellent green color purity.


Author(s):  
Heming Hu ◽  
Xindan Zhang ◽  
Miaomiao Gu ◽  
Yufei Liu ◽  
Lianxi Jia ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document