S. Varro et F. Ehlotzky, COHERENT PHASE-CONTROL OF FREE-FREE TRANSITIONS IN BICHROMATIC LASER FIELDS, Journal of physics. B, Atomic molecular and optical physics, 28(8), 1995, pp. 1613-1622
We consider the coherent phase control of the nonlinear cross sections
of induced and inverse bremsstrahlung in a powerful bichromatic laser
field. The two field components have frequencies r omega and s omega,
where r and s are small positive integers, and the relative phase psi
of both components can be changed arbitrarily. Amending our earlier w
ork on this problem (1993 Phys. Rev. A 47 715, 1993 Opt. Commun. 99 17
7) we show that for the ratios r:s = 1:2, 1:3 and 2:3 the phase-depend
ent changes of the free-free cross sections are quite appreciable, whe
reas for increasing values of s the phase dependence gradually disappe
ars, assuming both field components have the same intensity. If, howev
er, the intensity of the harmonic field component is considerably incr
eased, phase dependent effects again show up even for larger values of
s.