In Fig. 2 we decompose the emission spectrum of
as-deposited film into five Gaussian components of various C-H
vibrational modes according to the band assignment in the literatures
on amorphous carbon (Dischler et al. [1983]; Bounouh et al. [1995]).
The band centered at 3.30 m is assigned to the
aromatic sp2 CH stretching mode blended with the olefinic sp2CH2. The bands at 3.38, 3.42, 3.48
m are due to symmetric and
antisymmetric stretching C-H vibrations in sp3 CH2 and CH3chemical groups. The assignment of the 3.53
m band is somewhat
uncertain.
In Fig. 3 we present the overall thermal emission of QCC
samples before and after the thermal annealing at 740 K. The CaF2substrates used in the measurement have very low emissivity and no
spectral features in the wavelength region, and furthermore we cancel
out the minor contribution due to the substrate by subtracting its
spectrogram from that of the QCC sample. Thus we consider the
emissions observed here are certainly originated from QCC material
itself. The absolute intensity of the QCC emission is calibrated
by blackbody radiation of room temperature measured in the same
configuration. Note that the QCC sample before and after the annealing
is not equal in quantity. The emission features at
m are
by far strong in the as-deposited QCC.
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