  Chaotic instanton approach is used to describe dynamical tunneling in kicked
double well system. Effective Hamiltonian for the kicked system is obtained
using matrix expansion formula for operator exponent and exploited to construct
an approximation for chaotic instanton solution. This approximation is used for
derivation of the ground quasienergy splitting dependence on both the
perturbation strength and frequency. Results of numerical calculations for
corresponding ground quasienergy splitting dependencies based on Floquet theory
are in good agreement with the derived analytical formula in a wide range of
perturbation parameters.
