Descending Infrared Transmission Spectra of CdZnTe Substrates Due to Surface Roughness

ABSTRACTTwo low temperature metalorganic chemical vapor deposition growth techniques, the pre-cracking method and the plasma enhanced method, will be discussed. The pre-cracking technique enables one to grow high quality epitaxial Hg1−xCdxTe on CdTe or CdZnTe substrates at temperatures around 200–250°C. HgTe-CdTe superlattices with sharp interfaces have also been fabricated. Furthermore, for the first time, we have demonstrated that ternary Hg1−xCdTe compounds and HgTe-CdTe superlattices can be successfully grown by the plasma enhanced process at temperatures as low as 135 to 150°C. Material properties such as surface morphology, infrared transmission, Hall mobility, and interface sharpness will be presented.

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Retrieval of trace gases from aerosol-influenced infrared transmission spectra observed by low-spectral-resolution Fourier-transform spectrometers

Applied Optics ◽

10.1364/ao.44.000455 ◽

2005 ◽

Vol 44 (3) ◽

pp. 455 ◽

Cited By ~ 2

Author(s):

Nobuyuki Uemura ◽

Satoshi Kuriki ◽

Koji Nobuta ◽

Tatsuya Yokota ◽

Hideaki Nakajima ◽

...

Keyword(s):

Fourier Transform ◽

Spectral Resolution ◽

Trace Gases ◽

Transmission Spectra ◽

Infrared Transmission

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Localized surface plasmons in structures with linear Au nanoantennas on a SiO2/Si surface

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.7.145 ◽

2016 ◽

Vol 7 ◽

pp. 1519-1526 ◽

Cited By ~ 4

Author(s):

Ilya A Milekhin ◽

Sergei A Kuznetsov ◽

Ekaterina E Rodyakina ◽

Alexander G Milekhin ◽

Alexander V Latyshev ◽

...

Keyword(s):

Penetration Depth ◽

Surface Plasmons ◽

Infrared Absorption ◽

Transmission Spectra ◽

Localized Surface Plasmons ◽

Optical Phonons ◽

Infrared Transmission ◽

Phonon Modes ◽

Electromagnetic Simulations

The study of infrared absorption by linear gold nanoantennas fabricated on a Si surface with underlying SiO2 layers of various thicknesses allowed the penetration depth of localized surface plasmons into SiO2 to be determined. The value of the penetration depth derived experimentally (20 ± 10 nm) corresponds to that obtained from electromagnetic simulations (12.9–30.0 nm). Coupling between plasmonic excitations of gold nanoantennas and optical phonons in SiO2 leads to the appearance of new plasmon–phonon modes observed in the infrared transmission spectra the frequencies of which are well predicted by the simulations.

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Retrieval of stratospheric aerosol size and composition information from solar infrared transmission spectra

Applied Optics ◽

10.1364/ao.42.002140 ◽

2003 ◽

Vol 42 (12) ◽

pp. 2140 ◽

Cited By ~ 6

Author(s):

Helen M. Steele ◽

Annmarie Eldering ◽

Bhaswar Sen ◽

Geoffrey C. Toon ◽

Franklin P. Mills ◽

...

Keyword(s):

Stratospheric Aerosol ◽

Transmission Spectra ◽

Infrared Transmission

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Infrared Transmission Spectra of Carbonate Minerals

10.1007/978-94-011-2120-0 ◽

1993 ◽

Cited By ~ 42

Author(s):

G. C. Jones ◽

B. Jackson

Keyword(s):

Transmission Spectra ◽

Infrared Transmission ◽

Carbonate Minerals

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Properties of sub-Neptune atmospheres: TOI-270 system

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa1198 ◽

2020 ◽

Vol 495 (1) ◽

pp. 962-970

Author(s):

J Chouqar ◽

Z Benkhaldoun ◽

A Jabiri ◽

J Lustig-Yaeger ◽

A Soubkiou ◽

...

Keyword(s):

Molecular Weight ◽

Signal To Noise Ratio ◽

Spectral Features ◽

Transmission Spectra ◽

Infrared Transmission ◽

Signal To Noise ◽

Space Telescope ◽

Molecular Features ◽

James Webb Space Telescope ◽

Mean Molecular Weight

ABSTRACT We investigate the potential for the James Webb Space Telescope (JWST) to detect and characterize the atmospheres of the sub-Neptunian exoplanets in the TOI-270 system. Sub-Neptunes are considered more likely to be water worlds than gas dwarfs. We model their atmospheres using three atmospheric compositions – two examples of hydrogen-dominated atmospheres and a water-dominated atmosphere. We then simulate the infrared transmission spectra of these atmospheres for JWST instrument modes optimized for transit observation of exoplanet atmospheres: NIRISS, NIRSpec, and MIRI. We then predict the observability of each exoplanet’s atmosphere. TOI-270c and d are excellent targets for detecting atmospheres with JWST transmission spectroscopy, requiring only 1 transit observation with NIRISS, NIRSpec, and MIRI; higher signal-to-noise ratio can be obtained for a clear H-rich atmosphere. Fewer than three transits with NIRISS and NIRSpec may be enough to reveal molecular features. Water-dominated atmospheres require more transits. Water spectral features in water-dominated atmospheres may be detectable with NIRISS in two or three transits. We find that the detection of spectral features in a cloudy, H-rich atmosphere does not require integrations as long as those required for the water-dominated atmosphere, which is consistent with the differences in atmospheric mean molecular weight. TOI-270c and d could be prime targets for JWST transit observations of sub-Neptune atmospheres. These results provide useful predictions for observers who may propose to use JWST to detect and characterize the TOI-270 planet atmospheres.

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