  The fate of entanglement of spins for two heavy constituents of a bound state
moving in a strong laser field is analyzed within the semiclassical approach.
The bound state motion as a whole is considered classically beyond the dipole
approximation and taking into account the magnetic field effect by using the
exact solution to the Newton equation. At the same time the evolution of
constituent spins under the laser influence is studied quantum mechanically.
The spin density matrix is determined as solution to the von Neumann equation
with the effective Hamiltonian, describing spin-laser interaction along the
bound state classical trajectory. Based on the solution, the dynamics of
concurrence of spins is calculated for the maximally entangled Werner states as
well as for an initially uncorrelated state.
