0000000000934776
AUTHOR
A. S. De Castro
Analytically solvable 2×2 PT -symmetry dynamics from su(1,1)-symmetry problems
A protocol for explicitly constructing the exact time-evolution operators generated by $2\ifmmode\times\else\texttimes\fi{}2$ time-dependent $PT$-symmetry Hamiltonians is reported. Its mathematical applicability is illustrated with the help of appropriate examples. The physical relevance of the proposed approach within gain-loss system scenarios, like two coupled waveguides, is discussed in detail.
Classes of Exactly Solvable Generalized Semi-Classical Rabi Systems
The exact quantum dynamics of a single spin-1/2 in a generic time-dependent classical magnetic field is investigated and compared with the quantum motion of a spin-1/2 studied by Rabi and Schwinger. The possibility of regarding the scenario studied in this paper as a generalization of that considered by Rabi and Schwinger is discussed and a notion of time-dependent resonance condition is introduced and carefully legitimated and analysed. Several examples help to disclose analogies and departures of the quantum motion induced in a generalized Rabi system with respect to that exhibited by the spin-1/2 in a magnetic field precessing around the $z$-axis. We find that, under generalized resonanc…