scholarly journals Bulk-micromachined tunable Fabry–Perot microinterferometer for the visible spectral range

1999 ◽  
Vol 76 (1-3) ◽  
pp. 191-196 ◽  
Author(s):  
J.H. Correia ◽  
M. Bartek ◽  
R.F. Wolffenbuttel
2007 ◽  
Author(s):  
G. V. Sinitsyn ◽  
S. P. Apanasevich ◽  
A. V. Lyakhnovich ◽  
A. V. Sukhadolau

2019 ◽  
Vol 12 (1) ◽  
pp. 735-747 ◽  
Author(s):  
Jonas Kuhn ◽  
Ulrich Platt ◽  
Nicole Bobrowski ◽  
Thomas Wagner

Abstract. Many processes in the lower atmosphere including transport, turbulent mixing and chemical conversions happen on timescales of the order of seconds (e.g. at point sources). Remote sensing of atmospheric trace gases in the UV and visible spectral range (UV–Vis) commonly uses dispersive spectroscopy (e.g. differential optical absorption spectroscopy, DOAS). The recorded spectra allow for the direct identification, separation and quantification of narrow-band absorption of trace gases. However, these techniques are typically limited to a single viewing direction and limited by the light throughput of the spectrometer set-up. While two-dimensional imaging is possible by spatial scanning, the temporal resolution remains poor (often several minutes per image). Therefore, processes on timescales of seconds cannot be directly resolved by state-of-the-art dispersive methods. We investigate the application of Fabry–Pérot interferometers (FPIs) for the optical remote sensing of atmospheric trace gases in the UV–Vis spectral range. By choosing a FPI transmission spectrum, which is optimised to correlate with narrow-band (ideally periodic) absorption structures of the target trace gas, column densities of the trace gas can be determined with a sensitivity and selectivity comparable to dispersive spectroscopy, using only a small number of spectral channels (FPI tuning settings). Different from dispersive optical elements, the FPI can be implemented in full-frame imaging set-ups (cameras), which can reach high spatio-temporal resolution. In principle, FPI correlation spectroscopy can be applied for any trace gas with distinct absorption structures in the UV–Vis range. We present calculations for the application of FPI correlation spectroscopy to SO2, BrO and NO2 for exemplary measurement scenarios. In addition to high sensitivity and selectivity we find that the spatio temporal resolution of FPI correlation spectroscopy can be more than 2 orders of magnitude higher than state-of-the-art DOAS measurements. As proof of concept we built a 1-pixel prototype implementing the technique for SO2 in the UV. Good agreement with our calculations and conventional measurement techniques is demonstrated and no cross sensitivities to other trace gases are observed.


Sensors ◽  
2021 ◽  
Vol 21 (8) ◽  
pp. 2758
Author(s):  
Alberto Taffelli ◽  
Sandra Dirè ◽  
Alberto Quaranta ◽  
Lucio Pancheri

Photodetectors based on transition metal dichalcogenides (TMDs) have been widely reported in the literature and molybdenum disulfide (MoS2) has been the most extensively explored for photodetection applications. The properties of MoS2, such as direct band gap transition in low dimensional structures, strong light–matter interaction and good carrier mobility, combined with the possibility of fabricating thin MoS2 films, have attracted interest for this material in the field of optoelectronics. In this work, MoS2-based photodetectors are reviewed in terms of their main performance metrics, namely responsivity, detectivity, response time and dark current. Although neat MoS2-based detectors already show remarkable characteristics in the visible spectral range, MoS2 can be advantageously coupled with other materials to further improve the detector performance Nanoparticles (NPs) and quantum dots (QDs) have been exploited in combination with MoS2 to boost the response of the devices in the near ultraviolet (NUV) and infrared (IR) spectral range. Moreover, heterostructures with different materials (e.g., other TMDs, Graphene) can speed up the response of the photodetectors through the creation of built-in electric fields and the faster transport of charge carriers. Finally, in order to enhance the stability of the devices, perovskites have been exploited both as passivation layers and as electron reservoirs.


2014 ◽  
Vol 90 (12) ◽  
Author(s):  
Bivas Saha ◽  
Gururaj V. Naik ◽  
Sammy Saber ◽  
Cem Akatay ◽  
Eric A. Stach ◽  
...  

2021 ◽  
Vol 103 (3) ◽  
Author(s):  
V. S. Gerasimov ◽  
A. E. Ershov ◽  
R. G. Bikbaev ◽  
I. L. Rasskazov ◽  
I. L. Isaev ◽  
...  

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