Quantum dynamics of a two-level system under extrenal field
A. M. Korostił, Ju. Korostil
Abstract
We present exact analytic solutions for non-linear quantum dynamics of \n twolevel \nsystem (TLS) subject to \n periodic-in-time external field. >n constructing the \nexactly solvable models, we use \n approach where the form of external perturbation \nis chosen to preserve \nn integrability constraint, which yields \n single non-linear \ndifferential equation for the ac-field. solution to this equation is expressed in terms \nof Jacobi elliptic functions with three independent parameters that allows n to \nchoose the frequency, average value, and amplitude of the time-dependent field at \nwill. This form of the ac-drive is especially relevant to the problem of dynamics of \nTLS charge defects that cause dielectric losses ?n superconducting qubits.