Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Efficient single-cycle pulse compression of an ytterbium fiber laser at
  10 MHz repetition rate   Over the past years, ultrafast lasers with average powers in the 100 W range
have become a mature technology, with a multitude of applications in science
and technology. Nonlinear temporal compression of these lasers to few- or even
single-cycle duration is often essential, yet still hard to achieve, in
particular at high repetition rates. Here we report a two-stage system for
compressing pulses from a 1030 nm ytterbium fiber laser to single-cycle
durations with 5 ${\mu}$J output pulse energy at 9.6 MHz repetition rate. In
the first stage, the laser pulses are compressed from 340 to 25 fs by spectral
broadening in a krypton-filled single-ring photonic crystal fiber (SR-PCF),
subsequent phase compensation being achieved with chirped mirrors. In the
second stage, the pulses are further compressed to single-cycle duration by
soliton-effect self-compression in a neon-filled SR-PCF. We estimate a pulse
duration of ~3.4 fs at the fiber output by numerically back-propagating the
measured pulses. Finally, we directly measured a pulse duration of 3.8 fs (1.25
optical cycles) after compensating (using chirped mirrors) the dispersion
introduced by the optical elements after the fiber, more than 50% of the total
pulse energy being in the main peak. The system can produce compressed pulses
with peak powers >0.6 GW and a total transmission exceeding 70%.

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The categories of this paper are: funct-an
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The categories of this paper are: supr-con
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The categories of this paper are: cmp-lg
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The categories of this paper are: econ
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The categories of this paper are: hep-lat
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The categories of this paper are: atom-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: chem-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: math-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: eess
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The categories of this paper are: q-fin
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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: comp-gas