Frequency conversion of broad-bandwidth laser light

The efficacy of angular spectral dispersion by a grating as a means of improving the frequency conversion efficiency of broad-bandwidth laser light is investigated. It is shown that when the bandwidth arises from phase modulation, the zero-bandwidth conversion efficiency can be recovered in this way if the modulation is sufficiently slow, and that the frequency bandwidth is multiplied by the same factor as the frequency. When the bandwidth is due to amplitude modulation, the method is less effective. The theory is illustrated by calculations of third-harmonic generation in KDP.<
>