  We describe dynamics of spin and valley transitions driven by alternating
electric fields in quantum dots defined electrostatically within semiconducting
carbon nanotubes (CNT). We use the tight-binding approach to describe the
states localized within a quantum dot taking into account the circumferential
spin-orbit interaction due to the s-p hybridization and external fields. The
basis of eigenstates localized in the quantum dot is used in the solution of
the time-dependent Schroedinger equation for description of spin flips and
inter-valley transitions that are driven by periodic perturbation in the
presence of coupling between the spin, valley and orbital degrees of freedom.
Besides the first order transitions we find also fractional resonances. We
discuss the transition rates with selection rules that are lifted by atomic
disorder and the bend of the tube. We demonstrate that the electric field
component perpendicular to the axis of the CNT activates spin transitions which
are otherwise absent and that the resonant spin-flip time scales with the
inverse of the electric field.
