Superfluorescence from degenerate media (A)

K. Kitano, T. Kobayashi, H. Maeda

Nikolay N. Bogolubov, A.S. Shumovsky, Igor K. Kudryavtsev +1 more

J.A. Hermann

The emission of radiation from a spatially extended amplifying medium is shown to exhibit new coherence effects when the medium is modeled by inverted atoms which possess a degeneracy allowing Q(J) transitions. In particular, it is predicted that media of this type for which J=2 can emit leading pulses which are doubly peaked or asymmetric within both the regimes of superfluorescence and oscillating fluorescence. Dissipative processes can radically alter the character of the emission; an output consisting of two well-separated pulses appears feasible, but the precise behavior in the present model depends upon the magnitude of the field losses and the initiation statistics.

Jagdish Rai, Charles M. Bowden

We have studied the quantum-statistical properties of superfluorescence (SF) and amplified spontaneous emission (ASE) for dense media (media of densities corresponding to many atoms, on the average, within a cubic resonance wavelength). We use the Langevin equations of motion, obtained from a fully quantized model that takes into account induced near dipole-dipole interactions associated with dense media, together with the coupled Maxwell equation, to formulate a stochastic calculation ensemble. Quantum Monte Carlo methods are used in conjunction with the stochastic model, to conduct a statistical analysis of phase waves for this system. Results are presented for the phase-wave density, delay time, and peak-intensity fluctuations. The transition from SF to ASE is treated using the stochastic model.

Fritz Haake

Algis S. Piskarskas, A. Stabinis, Virgilijus Vaičaitis

Summary form only given. The investigations of nonlinear processes in various media pumped by Bessel beams are of broad interest due to the directivity of generated radiation. In this paper we present the results of an experiment, where the essential modification of angular structure of the four-photon parametric superfluorescence is demonstrated in sodium vapour pumped by two Bessel beams of different frequencies.