Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A simple, picojoule-sensitive ultraviolet autocorrelator based on
  two-photon conductivity in sapphire   We present a simple autocorrelator for ultraviolet pulses based on two-photon
conductivity in a bench-top fabricatable sapphire sensor. We perform
measurements on femtosecond 226 - 278 nm ultraviolet pulses from the third and
fourth harmonics of a standard 76 MHz titanium sapphire oscillator and
picosecond 266 nm pulses from the fourth harmonic of a 1064 nm 50 MHz neodymium
vanadate oscillator. Our device is sensitive to 2.6 pJ ultraviolet pulses with
peak powers below 20 W. These results represent the lowest measured
autocorrelation peak powers by over one order of magnitude for a system with no
reference pulse in the deep ultraviolet ( < 300 nm). The autocorrelator can
potentially support UV pulse lengths from 50 fs - 10's of picoseconds.

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The categories of this paper are: quant-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: plasm-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: math
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The categories of this paper are: supr-con
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The categories of this paper are: hep-th
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The categories of this paper are: econ
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The categories of this paper are: nlin
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The categories of this paper are: hep-ex
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The categories of this paper are: cmp-lg
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The categories of this paper are: cond-mat
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The categories of this paper are: nucl-ex
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The categories of this paper are: nucl-th
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The categories of this paper are: ao-sci
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The categories of this paper are: alg-geom