中央研究院 原子與分子科學研究所

Using rare-gas ions as the interacting medium, phase-matched high-order harmonic generation up to 1-keV
hard x ray can be achieved by balancing the negative plasma dispersion and Gouy phase shift with the
positive, intensity-dependent, intrinsic dipole phase variation. The time-dependent phase-matching condition
automatically gates the harmonic output to an isolated attosecond pulse. The estimated pulse duration is as short
as 120 as.