Scattering for super-radiation

M. T. Turaev

Martin W. Sørensen, Anders Søndberg Sørensen

We present a three-dimensional theory of stimulated Raman scattering (SRS) or super-radiance. In particular we address how the spatial and temporal properties of the generated SRS beam or Stokes beam of radiation depends on the spatial properties of the gain medium. Maxwell equations for the Stokes field operators and of the atomic operators are solved analytically and a correlation function for the Stokes field is derived. In the analysis we identify a super-radiating part of the Stokes radiation that exhibit beam characteristics. We show how the intensity in this beam builds up in time and at some point largely dominates the total Stokes radiation of the gain medium. We show how the SRS depends on the Fresnel number and the optical depth and that in fact these two factors are the only factors describing the coherent radiation.

Hari Prakash

Resonant scattering of am intense beam of radiation by an arbitrary number of atoms contained in a volume whose dimensions are small as compared to the radiation wavelength is studied. It is seen that the scattered radiation is an equally spaced triplet whose middle frequency is equal to the incident frequency. Counting rates exact to all orders in incident intensity are obtained. Special cases of (i) atoms in ground state, (ii) atoms in excited state, (iii) assembly of atoms in super-radiant state, and (iv) assembly of atoms in thermal equlibrium are studied.

Edward B. Manoukian

V.B. Berestetskii, E.M. LIFSHITZ, Лев П. Питаевский

K. Cho, Tomoe Ikawa

A systematic study is made by means of a microscopic nonlocal response theory about the enhancement mechanisms of the optical signals of resonant matter units in various arrangements, where the lattice constant in one direction allows Bragg scattering. Considering that the radiative decay width is a general measure of the coupling strength, we study (a) its size-enhancement and saturation, (b) its speed-up effect due to Bragg scattering, and (c) a super-enhancement effect due to the combination of (a) and (b).