Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Bright subcycle XUV pulse from a single dense relativistic electron
  sheet   Relativistic electrons are prodigious sources of photons. Beyond classical
accelerators, ultra-intense laser interactions are of particular interest as
they allow the coherent motion of relativistic electrons to be controlled and
exploited as sources of radiation. Under extreme laser conditions theory
predicts that isolated free relativistic electron sheets (FRES) can be produced
and exploited for the production of a new class of radiation - unipolar extreme
ultraviolet(XUV) pulses. However, the combination of extremely rapid rise-time
and highest peak intensity in these simulations is still beyond current laser
technology. We demonstrate a route to isolated FRES with existing lasers by
exploiting relativistic transparency to produce an ultra-intense pulse with a
steep rise time. When such an FRES interacts with a second, oblique target foil
the electron sheet is rapidly accelerated ('kicked'). The radiation signature
and simulations demonstrate that a single, nanometer thick FRES was produced.
The experimental observations together with our theoretical modeling suggest
the production of the first unipolar (half-cycle) pulse in the XUV - an
achievement that has so far only been realized in the terahertz spectral
domain.

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The categories of this paper are: patt-sol
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: econ
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The categories of this paper are: adap-org
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The categories of this paper are: mtrl-th
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The categories of this paper are: hep-lat
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The categories of this paper are: bayes-an
2
The categories of this paper are: math
30
The categories of this paper are: q-alg
13
The categories of this paper are: quant-ph
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The categories of this paper are: q-bio
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The categories of this paper are: astro-ph
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The categories of this paper are: math-ph
31
The categories of this paper are: ao-sci