Luminescence from Hydrogenated Amorphous Carbon and Extended Red Emission from Nebulae

1997 ◽  
Vol 482 (2) ◽  
pp. 866-869 ◽  
Author(s):  
W. W. Duley ◽  
S. Seahra ◽  
D. A. Williams
1989 ◽  
Vol 135 ◽  
pp. 141-146
Author(s):  
W. W. Duley

Various sources of non-equilibrium radiation from interstellar dust are discussed. It is shown that the existence of cirrus emission at 12 and 25 μm is consistent with the presence of amorphous carbon dust and arises from thermal spikes within ≃ 10å subvolumes of normal (0.01-0.1 μm radius) dust grains. The 3.28 μm unidentified infrared (UIR) feature also arises in this way, as the radiative relaxation of high energy vibrational modes accompanying a thermal spike in hydrogenated amorphous carbon. Extended red emission (ERE) and near-infrared (NIR) emission are also discussed and are postulated to originate as edge and defect luminescence from HAC solids with bandgaps Eg ≲ 2.5eV.


2009 ◽  
Vol 23 (09) ◽  
pp. 2159-2165 ◽  
Author(s):  
SUDIP ADHIKARI ◽  
MASAYOSHI UMENO

Nitrogen incorporated hydrogenated amorphous carbon (a-C:N:H) thin films have been deposited by microwave surface-wave plasma chemical vapor deposition on silicon and quartz substrates, using helium, methane and nitrogen ( N 2) as plasma source. The deposited a-C:N:H films were characterized by their optical, structural and electrical properties through UV/VIS/NIR spectroscopy, Raman spectroscopy, atomic force microscope and current-voltage characteristics. The optical band gap decreased gently from 3.0 eV to 2.5 eV with increasing N 2 concentration in the films. The a-C:N:H film shows significantly higher electrical conductivity compared to that of N 2-free a-C:H film.


Coatings ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1269
Author(s):  
Chin-Chiuan Kuo ◽  
Chun-Hui Lin ◽  
Jing-Tang Chang ◽  
Yu-Tse Lin

Chromium-carbon films were deposited by utilizing reactive high-power impulse magnetron sputtering at different mixture ratios of ethyne and argon atmosphere, and different substrate bias voltages and deposition temperature, with the same pulse frequency, duty cycle, and average power. The microstructure and mechanical properties of the obtained films were compared. The films consist of amorphous or nanocrystalline chromium carbide, hydrogenated amorphous carbon, and minor α-chromium phase. Decreasing the fraction of ethyne increases the content of the α-chromium phase but decreases hydrogenated amorphous carbon phase. The film’s hardness increases by enhancing the negative substrate bias and raising the deposition temperature, which could be attributed to the increase of film density and the Hall–Petch strengthening effect induced by the nanoscale crystallization of the amorphous carbide phase.


2014 ◽  
Vol 258 ◽  
pp. 219-224 ◽  
Author(s):  
S.M.M. Dufrène ◽  
F. Cemin ◽  
M.R.F. Soares ◽  
C. Aguzzoli ◽  
M.E.H. Maia da Costa ◽  
...  

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