Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: High-order harmonic generation driven by metal nanotip photoemission:
  theory and simulations   We present theoretical predictions of high-order harmonic generation (HHG)
resulting from the interaction of short femtosecond laser pulses with metal
nanotips. It has been demonstrated that high energy electrons can be generated
using nanotips as sources; furthermore the recollision mechanism has been
proven to be the physical mechanism behind this photoemission. If recollision
exists, it should be possible to convert the laser-gained energy by the
electron in the continuum in a high energy photon. Consequently the emission of
harmonic radiation appears to be viable, although it has not been
experimentally demonstrated hitherto. We employ a quantum mechanical time
dependent approach to model the electron dipole moment including both the laser
experimental conditions and the bulk matter properties. The use of metal tips
shall pave a new way of generating coherent XUV light with a femtosecond laser
field.

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The categories of this paper are: astro-ph
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The categories of this paper are: dg-ga
11
The categories of this paper are: hep-lat
32
The categories of this paper are: atom-ph
27
The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex
4
The categories of this paper are: cond-mat
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
0
The categories of this paper are: hep-ph
13
The categories of this paper are: quant-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: q-fin
12
The categories of this paper are: nucl-th
25
The categories of this paper are: patt-sol
26
The categories of this paper are: bayes-an