Published online by Cambridge University Press: 30 July 2001
We report the results of measurements aimed to check the phase lock of time-delayed, collinear, harmonic pulses and to verify the possibility of performing Ramsey-like spectroscopy in the XUV. We demonstrate that for harmonics of medium order and for the peak intensities available with our laser system, the generation of collinear phase-locked harmonic pulses is indeed possible and that such pulses can be used to achieve high-resolution spectroscopy in the short-wavelength region.