Transition from superfluorescence to amplified spontaneous emission (A)

Farrès P. Mattar

Martin F. H. Schuurmans, D. Polder

Martin F. H. Schuurmans

Jagdish Rai, Charles M. Bowden

M.H.F. Overwijk, J. I. Dijkhuis, H. W. de Wijn

Superfluorescence and amplified spontaneous emission of 29-${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ phonons are observed following inversion of the E\ifmmode\bar\else\textasciimacron\fi{}${(}^{2}$E)-2A\ifmmode\bar\else\textasciimacron\fi{}${(}^{2}$E) acoustic transition of ${\mathrm{Cr}}^{3+}$ in ruby. The conditions for both of these manifestations of phonon avalanches are selected via the ${\mathrm{Cr}}^{3+}$ concentration. Superfluorescence is described in terms of a pendulum equation of the acoustic Bloch vector. Rate equations of the level and phonon populations account for amplified spontaneous emission.

F. P. Mattar, C. M. Bowden, Chi C. Sung