Quantum branching processes and nonlinear dynamics of multiquantum systems

V. R. Struleckaja

The algebraic approach to the description and representation of multiquantum (multicomponent) systems discussed in the present paper continues the approach developed in [5,9–12]. That is based on the generating multicomponent -state functional and the nonlinear completely positive map [3] functional method which extends in a natural way the variety of the processes regarded as quantum stochastic processes [2], including nonlinear ones with interaction in the system. The dynamics of such systems is considered in the Markovian approximation; the theory and classification of the corresponding “master equations” was constructed in [13]. In the nonlinear case we obtain in a natural way a nonlinear extension of the basic constructions and results of the representation theory and an extension to nonlinear structures (state and mapping) [3,81 which are good tools to describe systems with interaction.

V. P. Belavkin

F.M. Ciaglia, F. Di Cosmo, A. Figueroa +5 more

Małgorzata Jeleń, Wojciech Froncisz

A method to excite multiquantum transitions in a two-level system by application of continuous irradiation with a four-frequency microwave field is presented. The generated signal is composed of many intermodulation sidebands at different frequencies, which arise from the multiquantum transitions. These processes involve an odd number of photons, that are absorbed from, or emitted to two, three, or four fields. The correspondence between the frequency spectrum of the signal and possible pathways of multiquantum processes is found with recourse to the many mode Floquet theory. The reported experiments demonstrate the multiquantum origin of the detected intermodulation sidebands and their properties.

Salman Habib