2 Linear Equations 14 2.1 Matrix Exponentials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 2.2 Normal Forms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 2.3 Non-Autonomous Linear Equations . . . . . . . . . . . . . . . . . . . . . 19 2.4 Inhomogeneous Linear Equations . . . . . . . . . . . . . . . . . . . . . . 20 2.5 Stability and Boundedness . . . . . . ....

For time-periodical quantum systems generalized Floquet operator is found to be integral of motion.Spectrum of this invariant is shown to be quasienergy spectrum.Analogs of invariant Flo-quet operators are found for nonperiodical systems with several characteristic times.Generalized quasienergy states are introduced for these systems. Geometrical phase is shown to be integral of motion. Quantum...

We construct a class of exact commensurate and incommensurate standing wave (SW) solutions in a piecewise smooth analogue of the discrete non-linear Schrödinger (DNLS) model and present their linear stability analysis. In the case of the commensurate SW solutions the analysis reduces to the eigenvalue problem of a transfer matrix depending parametrically on the eigenfrequency. The spectrum of e...

We study a system of three coherently coupled states, where one state is shifted periodically against the other two. We discover that this system possesses a dark Floquet state that has zero quasi-energy and negligible population at the intermediate state. This dark Floquet state manifests itself dynamically in terms of the suppression of inter-state tunneling, a phenomenon known as coherent de...

The dynamic response of an axially translating continuum subjected to the combined effects of a pair of spring supported frictional guides and axial acceleration is investigated; such systems are both non-conservative and gyroscopic. The continuum is modeled as a tensioned string translating between two rigid supports with a time dependent velocity profile. The equations of motion are derived w...

Using the parametrically driven harmonic oscillator as a working example, we study two different Markovian approaches to the quantum dynamics of a periodically driven system with dissipation. In the simpler approach, the driving enters the master equation for the reduced density operator only in the Hamiltonian term. An improved master equation is achieved by treating the entire driven system w...