GENERATION OF A HARMONIC QUASI-CONTINUUM FROM BEATING LASER FIELDS

We present simulations of the two-colour harmonic response of a one-di mensional model atom exposed to a superposition of two laser fields of varying relative intensities and of non-commensurate frequencies. We show that this interaction can be used to efficiently generate a quasi -continuum of very closely spaced harmonics and explain how such a sch eme can be implemented experimentally. We show how the generation proc ess can be described in terms of the beat frequencies between the two fields. Finally, we discuss the limitations of the 1 omega-3 omega int eraction (which has been studied extensively elsewhere).