Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Ultra-short-pulse high-average-power Megahertz-repetition-rate coherent
  extreme-ultraviolet light source   High harmonic generation (HHG) enables coherent extreme-ultraviolet (XUV)
radiation with ultra-short pulse duration in a table-top setup. This has
already enabled a plethora of applications. Nearly all of these applications
would benefit from a high photon flux to increase the signal-to-noise ratio and
decrease measurement times. In addition, shortest pulses are desired to
investigate fastest dynamics in fields as diverse as physics, biology,
chemistry and material sciences. In this work, the up-to-date most powerful
table-top XUV source with 12.9 mW in a single harmonic line at 26.5 eV is
demonstrated via HHG of a frequency-doubled and post-compressed fibre laser. At
the same time sub-6 fs XUV pulse duration allows accessing ultrafast dynamics
with an order of magnitude higher photon flux than previously demonstrated.
This concept will greatly advance and facilitate applications of XUV radiation
in science and technology and enable photon-hungry ultrafast studies.

24
The categories of this paper are: dg-ga
34
The categories of this paper are: chem-ph
6
The categories of this paper are: astro-ph
16
The categories of this paper are: stat
4
The categories of this paper are: cond-mat
26
The categories of this paper are: bayes-an
7
The categories of this paper are: hep-th
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
8
The categories of this paper are: hep-ex
13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph
29
The categories of this paper are: funct-an
19
The categories of this paper are: eess
20
The categories of this paper are: acc-phys