Surface states spectroscopy. Surface electromagnetic waves.
Physics of surfaces and two-dimensional systems as well as applied problems both stimulated the
development experimental studies of surfaces and interfaces. The choice of IR and Raman spectroscopy for these
purposes is explained by its nondestructive character, by the possibility of applications not only ultrahigh vacuum
(as is the case with electron spectroscopy methods) but also at high gas pressure above the surface.
The surface phonon-polaritons in more than 30 crystals of semiconductors and dielectrics were studied, the
influence of thin conducting and dielectric layers on the dispersion curves was analyzed [1]. The quenching of
surface polaritons by a metal film was discovered, for the first time the theoretically predicted surface polariton line
splitting in the resonance with transition layer phonon was confirmed, the root-square dependence of the splitting
value on thickness was shown. On this basis was proposed a new method of film’s thickness determination, when it
is less than visible light wavelength. The spectroscopy of surface polaritons was used for optical constants
determination of thin films and transition layers covering the dielectric crystals (metallic and “artificial dielectrics “
films [1], layers formed by the ion implantation of quartz surface).
For the first time the phenomenon of thermostimulated emission of surface polaritons was discovered and
an experimental method for surface polaritons dispersion curves determination (ZnSe single crystal and its films on
metals [2]) and for investigations of phase transitions [3] was proposed on the basis of this phenomenon.
We begin to use practically at the same time with American scientists the surface plasmons of metals 
surface electromagnetic waves (SEW)  as a spectroscopic mean for thin films on metals, using the CO 2 laser with
frequency tuning. Later the prisms  elements for SEW excitation  we substituted by “razor blade” and that
allowed us to develop interferometric method for determination optical constants of conducting materials, high
temperature superconductors as well as dielectrics in the “reststrahlen” range, where the phonon polaritons exist.
In the Laboratory the Raman spectroscopy of the surface
polaritons was developed. The dispersion, the frequency dependence of
intensity and the polarization properties of the surface polaritons in the
Raman spectra of GaP were studied [4]. For the first time were found
families of wave-guide modes of of p- and s-type below the TO
frequency (Fig. 2) and above the LO frequency and also one of low
branches of interference modes in the GaP film [5].
Fig. 1. The dependence of Raman scattering by the wave-guide pmodes of the low branch in GaP on the angle scattering.
For the first time were investigated the Raman spectra of ultrafine
amorphous superlattices Si-SiO2. The localization strengthening of TO
mode were revealed with the decrease of the SiO2 thickness. The extra
features in spectra were displayed that were assigned to the formation
of interface modes on the layer boundaries and effects of the
dimensional quantization (the folding of acoustical branches). New
bulk and surface phonon-plasmon modes were found in Raman spectra of porous semiconductor InP [6]. It is shown
that their appearance may be explained in approximation of the effective medium theory (modified Maxwell-Garnett
theory). It is found that the surface electric field in porous GaAs is responsible for the breakdown of the selection
rules not only for LO modes due to Frohlich mechanism, but also for TO modes due to the lowering of total
symmetry of near-surface layer in pores in presence of the surface electric field. An identification of side products
on the surface of the porous GaAs and GaSb obtained with electrochemical etching in the solution of various acids
was implemented by means of Raman spectroscopy.
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E.A.Vinogradov, G.N.Zhizhin, M.A.Moskalova, V.A.Yakovlev. Applications of Surface Polaritons for
Vibrational Spectroscopic Studies of Thin and Very Thin Films. Applied Spectroscopy Reviews, v.18(2),
171 (1982-83).
E.A.Vinogradov, G.N.Zhizhin.Thermally stimulated emission by surface oscillations of zinc selenide
crystal-lattice atoms. Jetp Lett..v.24(2), 71 (1976).
E.A.Vinogradov, G.N.Zhizhin, I.I.Khammadov. V.A.Yakovlev. Thermally stimulated radiation emitted by
surface polaritons in gadolinium molybdate in the vicinity of the phase transition. Sov.Phys.Solid
State(USA), v.23(2), 326(1981).
V.N.Denisov, B.N.Mavrin, V.B.Podobedov. Raman spectra by surface polaritons in the GaP crystal:
dispersion, intensity and the polarization property. Zh.Exp.Teor.Fiz., 92, 1855 (1987).
V.N.Denisov, T.A.Leskova, B.N.Mavrin, V.B.Podobedov. Raman spectra by waveguide and interference
modes in a GaP films. JETP, v.94, 261 (1988).
V.N.Denisov, B.N.Mavrin, V.A.Karavanski. New bulk and surface phonon-plasmon modes in Raman
spectra of porous n-InP. Phys.Lett., A259, 62 (1999).