DETERMINATION OF FLOQUET STATES AND QUASI-ENERGY BY CORRELATION FUNCTION

The Floquet spectrum generated by the use of time correlation function has been developed to extract the Floquet functions with Fourier transform method for wave function at integral multiples of optical period. The quasi-energy position and ionization width of those Floquet states have also been determined by least-squares fit method. Numerical calculation shows that the Fourier transform method is powerful and the resultant Floquet functions are in excellent agreement with that obtained by orthogonality projection method developed in our previous work.