scholarly journals 2D Perovskite Micro-optics Enabled by Direct Femtosecond-Laser Projection Lithography

2021 ◽  
Vol 2015 (1) ◽  
pp. 012075
Author(s):  
A. Cherepakhin ◽  
A. Zhizhchenko ◽  
A. Porfirev ◽  
A. Pushkarev ◽  
S. Makarov ◽  
...  

Abstract Using direct femtosecond-laser projection lithography in chemically synthesized CsPbBr3 perovskite microcrystals we demonstrate high-throughput fabrication of advanced binary microscale optical elements for nanofocusing as well as generation of high-order optical vortex beams. The obtained results highlight the CsPbBr3 microcrystals as a promising material for realization of various complicated 2D micro-optical elements and holograms that can be directly imprinted using non-destructive and practically relevant laser technologies.

Sensors ◽  
2020 ◽  
Vol 20 (16) ◽  
pp. 4550
Author(s):  
Huajian Liu ◽  
Brooke Bruning ◽  
Trevor Garnett ◽  
Bettina Berger

The accurate and high throughput quantification of nitrogen (N) content in wheat using non-destructive methods is an important step towards identifying wheat lines with high nitrogen use efficiency and informing agronomic management practices. Among various plant phenotyping methods, hyperspectral sensing has shown promise in providing accurate measurements in a fast and non-destructive manner. Past applications have utilised non-imaging instruments, such as spectrometers, while more recent approaches have expanded to hyperspectral cameras operating in different wavelength ranges and at various spectral resolutions. However, despite the success of previous hyperspectral applications, some important research questions regarding hyperspectral sensors with different wavelength centres and bandwidths remain unanswered, limiting wide application of this technology. This study evaluated the capability of hyperspectral imaging and non-imaging sensors to estimate N content in wheat leaves by comparing three hyperspectral cameras and a non-imaging spectrometer. This study answered the following questions: (1) How do hyperspectral sensors with different system setups perform when conducting proximal sensing of N in wheat leaves and what aspects have to be considered for optimal results? (2) What types of photonic detectors are most sensitive to N in wheat leaves? (3) How do the spectral resolutions of different instruments affect N measurement in wheat leaves? (4) What are the key-wavelengths with the highest correlation to N in wheat? Our study demonstrated that hyperspectral imaging systems with satisfactory system setups can be used to conduct proximal sensing of N content in wheat with sufficient accuracy. The proposed approach could reduce the need for chemical analysis of leaf tissue and lead to high-throughput estimation of N in wheat. The methodologies here could also be validated on other plants with different characteristics. The results can provide a reference for users wishing to measure N content at either plant- or leaf-scales using hyperspectral sensors.


2014 ◽  
Author(s):  
Konstantin Mishchik ◽  
Yannick Petit ◽  
Etienne Brasselet ◽  
Inka Manek-Hönninger ◽  
Nicolas Marquestaut ◽  
...  

1993 ◽  
Author(s):  
Vadim P. Veiko ◽  
Alexei K. Kromin ◽  
Evgeny B. Yakovlev

Nanophotonics ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 727-732
Author(s):  
Marco Piccardo ◽  
Antonio Ambrosio

AbstractThe purity of an optical vortex beam depends on the spread of its energy among different azimuthal and radial modes, also known as $\ell $- and p-modes. The smaller the spread, the higher the vortex purity and more efficient its creation and detection. There are several methods to generate vortex beams with well-defined orbital angular momentum, but only few exist allowing selection of a pure radial mode. These typically consist of many optical elements with rather complex arrangements, including active cavity resonators. Here, we show that it is possible to generate pure vortex beams using a single metasurface plate—called p-plate as it controls radial modes—in combination with a polarizer. We generalize an existing theory of independent phase and amplitude control with birefringent nanopillars considering arbitrary input polarization states. The high purity, sizeable creation efficiency, and impassable compactness make the presented approach a powerful complex amplitude modulation tool for pure vortex generation, even in the case of large topological charges.


Sign in / Sign up

Export Citation Format

Share Document