Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Mode-locked pulse oscillation of a self-resonating enhancement optical
  cavity   A power enhancement optical cavity is a compelling means of realizing a
pulsed laser with a high peak power and high repetition frequency, which is not
feasible using a simple amplifier scheme. However, a precise feedback system is
necessary for maintaining the narrow resonance condition of the optical cavity;
this has become a major technical issue in developing such cavities. We have
developed a new approach that does not require any active feedback system, by
placing the cavity in the outer loop of a laser amplifier. We report on the
first demonstration of a mode-locked pulse oscillation using the new system.

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The categories of this paper are: acc-phys
4
The categories of this paper are: cond-mat
17
The categories of this paper are: q-fin
8
The categories of this paper are: hep-ex
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The categories of this paper are: eess
24
The categories of this paper are: dg-ga
27
The categories of this paper are: comp-gas
13
The categories of this paper are: quant-ph
6
The categories of this paper are: astro-ph
11
The categories of this paper are: hep-lat
28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
21
The categories of this paper are: adap-org
2
The categories of this paper are: math