Dynamics of superradiance in a resonator

Ashat M. Basharov, G. G. Grigoryan, Yu.V. Orlov +3 more

N. S. Ginzburg, E. R. Golubyatnikova, Vl. V. Kocharovsky +1 more

Askhat M Basharov, Grigorii G Grigoryan, Nikolay V Znamenskiy +3 more

Experimental results and a theoretical model describing superradiance of praseodymium ions in the trifluoro lanthanum matrix at the 3 P 0 — 3 H 6 transition upon coherent excitation of the adjacent 3 H 4 — 3 P 0 transition are presented. It is found that when a superradiant medium is placed into a resonator, whose eigenfrequency is close to the superradiant transition ( 3 P 0 — 3 H 6 ) frequency, the superradiant pulse duration decreases and its modulation appears, which is independent of the resonator length. It is shown that these properties are qualitatively described within the framework of the mean-field model of coherent radiation of superradiant media in a resonator.

А. В. Андреев

Ashat M. Basharov, G. G. Grigoryan, Yu. V. Orlov +3 more

Experimental data and theoretical model concerning superradiant emission from the LaF3 medium doped with impurity praseodymium ions are presented in cases of free medium and when the medium is placed into resonator. The spiky structure of superradiance is registered and studied. When the medium is placed inside a cavity, a new channel of energy removal by superradiance related to the cavity mode appears; the old noncavity channels are preserved. The duration of superradiance in each channel is decreased and the modulation arises. These peculiarities of superradiance induced by the presence of resonator are explained on the basis of the developed mean-field theory.

Nikita E. Nefedkin, E. S. Andrianov, Alexander Pukhov +1 more

Abstract In this work we consider the dynamics of an ensemble of two-level atoms that interact with finite-width resonator mode. The superradiant burst occurs under a wide range of parameters in such a system. However, if the initial phase distribution of dipole moments of N two-level atoms is random, not all atoms take part in the superradiant process, but only the part of them that results in the intensity of supperradiance I ∼ N α , where α < 2 . In this paper we investigate the dependence of the parameter α on the resonator mode decay rate. It is shown that there is a critical value of resonator mode decay rate that divides two different regimes of superradiance. If the decay rate is lower than the critical rate, superradiance demonstrates a multi-peak character and the number of dipoles forming superradiant burst increases while α grows from 1 to 2. When the decay rate is larger than the critical value there is a single-peak superradiant regime. The delay time dependence on N changes from power to logarithmic law at the critical decay rate. The existence of the optimal value of resonator decay rate can be used for superradiance enhancement by a resonator with finite losses.