Light scattering studies at UNICAMP

摘要: We briefly report here current theoretical stud'es on light scattering spectroscopy at UNICAMP IFGW. INELASTIC SCATTERING OF RADIATION F^ OW A SOLID STATE PLASMA. Raman Scattering of light from a n-type semiconductor in the presence of a constant meynetic field has been analyzed for any orientation of the wavevector q transferred in the scattering livont relative to the magnetic field B0. Particular attention'. vas yiven to the high temperature case (T» T p) because of the interest arisen by experimental studies of scattering fro. r, a hot plasma."'A generalized Landau quasi-particle picture (GLQP) was used.'*'The Raman scattering cross section was expressed in terms of the fluctuation of the Landau quasi-p-'rticle density operator, p.'1*'The fluctuation of p induced by the scattering potential was obtained h>/solving the Generalized• pit Consistent Field (GSCF) transport equation.'4'The details of the calculation, together with a numerical application appropriate to the case of n doped GaAs are given el. ewhere.'*''For this particular case of a parabolic conduction band semiconductor, the intensity of light scattered from charge density fluctuations becomes proportional to tht imaginary part uf the inverse of the electron yas dielectric response function, e (q, u). riyure I shows the" dispersion curves"(Re É-0) for the cuupled hybrid mode first Bernstein mode, for q 0 and T» T p. The position of the peaks in the cont'sponclinj Raman spectra are shown. There is a reasonable agreement with the values of the roots of Re t 0 Details of lhe spectra «re given in Ref| 5|. We also discussed the effect of the Coulomb electron electron interaction on the …