This article is cited in
4 papers
Active spectroscopy of polaritons (phenomenological description)
D. N. Klyshko
Abstract:
An analysis is made of the contribution of three-photon cascade processes, involving polariton states, to four-photon processes in noncentrosymmetric crystals. It is shown that in the case of a sample which is opaque to
virtual polaritons this contribution is governed by the tensor
$\gamma_{\text{cas}}=\beta G\beta$ [
$\beta(\omega_0)$ the polarizability of the medium, which is a quadratic function of the field, and
$G(\omega_0k_0$), is the spectral polariton Green's function which is related by a one-to-one correspondence to the linear
polarizability
$\alpha(\omega_0)$]. Thus, the dependence of the effect in question on
$k_0$ is governed by the function
$G(k_0)$, and it can be used to determine the dispersion law of polaritons. The
dependence of the effect on
$\omega_0$ is considered using a single-pole approximation of the dispersion of polarizabilities. It is shown that the cascade processes make it possible to study [with the aid of
$\beta(\infty)$] matter resonances which are forbidden in the Raman scattering but which make a contribution to
$\alpha$.
UDC:
535.375:548
PACS:
71.36.+c,
78.20.Bh Received: 03.07.1974
Fulltext:
PDF file (980 kB)
