Phase matching with pulsed Bessel beams for high-order harmonic generation

We propose a different approach to obtain phase-matched generation of high-order harmonics based on the use of pulsed Bessel beams as pump pulses. By means of the ``coherence map'' technique, we show that it is possible to maximize the generation of a chosen harmonic of interest by properly adjusting the phase front tilt of the pulsed Bessel beam to compensate the mismatch arising from material and plasma dispersion and atomic phase.