| Summary: | 碩士 === 輔仁大學 === 物理研究所 === 82 === The main aim for the report lies in to explain the different
feature of first order Raman spectrum between crsytal and glass
in expriment,which crystal exhibit the discrete set of sharp
bands and glass continuous broad bands.To realize the
appearance,we must consider the condition of coupling of light
and vibration.In quantum mechanical theory,we consider the
situation of dielectric constant.We can derive cross section of
scattering throught space-time Fourier''s transformation of the
correlation function of the dielectric fluctuations.The result
of calculation appear that the first order Raman scattering of
crystal must obey the momentum selection rule,thus only some
special vibration modes participate in scattering. In glass,
the momentum selection rule breaks down,therefore all vibration
modes take part in scattering.For above reasons,we can explain
the feature of Raman spectrum of crystal and glass.
|
|---|
