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arXiv · 1612.04100

A temporal model for quasi-phase matching in high-order harmonic generation

Y. Tao·S. J. Goh·H. M. J. Bastiaens·P. J. M. van der Slot·S. G. Biedron·S. V. Milton·K. -J. Klaus
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Abstract

We present a model for quasi-phase matching (QPM) in high-order harmonic generation (HHG). Using a one-dimensional description, we analyze the time-dependent, ultrafast wave-vector balance to calculate the on-axis harmonic output versus time, from which we obtain the output pulse energy. Considering, as an example, periodically patterned argon gas, as may be provided with a grid in a cluster jet, we calculate the harmonic output during different time intervals within the drive laser pulse duration. We find that identifying a suitable single spatial period is not straightforward due to the complex and ultrafast plasma dynamics that underlies HHG at increased intensities. The maximum on-axis harmonic pulse energy is obtained when choosing the QPM period to phase match HHG at the leading edge of the drive laser pulse.

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Y. Tao, S. J. Goh, H. M. J. Bastiaens, P. J. M. van der Slot, S. G. Biedron, S. V. Milton, K. -J. Klaus. 2016-12-13. A temporal model for quasi-phase matching in high-order harmonic generation. https://doi.org/10.1364/oe.25.003621

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