LAUSR

We demonstrate the scanning and control of the carrier-envelope phases (CEPs) of two adjacent spectral components totally spanning more than one-octave in the short-wave infrared (SWIR) wavelength region by operating two individual acousto-optic programmable dispersive filters (AOPDFs) applied to each of the two spectral components. The total CEP shift of the synthesized sub-cycle pulse composed of the two spectral components is controlled with simultaneous scans of the two CEPs. The resultant error of the controlled CEP was 642 mrad, so that this technique is useful for searching zero CEP of the synthesized pulse with the maximum field amplitude. In addition, we conduct a closed feedback loop to compensate for the CEP fluctuation by using the two AOPDFs together. As a result, we succeed to reduce the rms error of the CEP from 399 mrad to 237 mrad.