Measurement of Fourier-synthesized optical waveforms

technique for determining the temporal envelope of an optical beam whose spectrum consists of n discrete, equally spaced frequency components. Four-wave mixing is employed to generate n−1 higher-frequency sidebands. The relative intensities of these sidebands, together with the intensities of the incident side-bands, determine the unknown relative phases of the incident beam. © 2005 Optical Society of America OCIS codes: 190.4380, 320.7100, 320.7110. Over the past several years it has been shown that molecular modulation can produce a collinear beam of mutually coherent sidebands that extend in fre-quency from the IR to the far UV.1–4 Adjusting the phases of these sidebands allows periodic optical waveforms with a prescribed temporal shape to be synthesized. In early experiments the temporal shape of the synthesized waveforms was measured by using multiphoton ionization.5 Recently, Shverdin et al.6 used a new technique fo