Superradiance of an extended layer of excited classical oscillators

N. S. Ginzburg, Alexander S. Sergeev

N. S. Ginzburg, Alexander S. Sergeev

Iu. A. Il'Inskii, N. S. Maslova

A. V. Pakhomov, Mikhail V. Arkhipov, Nikolay N. Rosanov +1 more

Here we demonstrate an unusual type of superradiance in an extended layer of a two-level medium excited by a pair of unipolar pulses. It is shown that, due to the interference of secondary waves emitted by the resonant medium, the response of such a layer in reflection represents a pair of half-cycle unipolar pulses of different polarity. They follow with a time delay proportional to the layer thickness. The source of such superradiance is a monopolar half-cycle pulse of the stopped polarization induced by the first excitation pulse and switched off by the second excitation pulse. The predicted effect can be used to control the shape of few- and subcycle pulses in resonant media.

Volodymyr M. Kuklin, D. N. Litvinov, A.E. Sporov

Rostislav M. Arkhipov, A. V. Pakhomov, Mikhail V. Arkhipov +1 more

Using the numerical solution of the system of equations for the amplitudes of bound states, together with the wave equation, we theoretically consider stopped polarization pulse superradiance upon excitation by a pair of half-period attosecond pulses in a thin layer of a five-level resonant medium, the parameters of which are the same as in a hydrogen atom. It is shown that in the case of a multilevel medium, at certain parameters of the exciting field, the superradiance pulse near the medium is also a single-cycle pulse, the shape of which is determined by the first time derivative of the stopped polarization pulse, as in the case when approximate low-level and classical models were used to describe the response of the medium. Keywords: superradiance, attosecond pulses, stopped polarization pulse, unipolar pulses, subcycle pulses.