Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Simple Single-Section Diode Frequency Combs   Frequency combs, broadband light sources whose spectra consist of coherent,
discrete modes, have become essential in many fields. Miniaturizing frequency
combs would be a significant advance in these fields, enabling the deployment
of frequency-comb based devices for diverse measurement and spectroscopy
applications. We demonstrate diode-laser based frequency comb generators. These
laser diodes are simple, electrically pumped, inexpensive and readily
manufactured. Each chip contains several dozen diode-laser combs. We measure
the time-domain output of a diode frequency comb to reveal the underlying
frequency dynamics responsible for the comb spectrum, conduct dual comb
spectroscopy of a molecular gas with two devices on the same chip, and
demonstrate that these combs can be battery powered.

2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
7
The categories of this paper are: hep-th
15
The categories of this paper are: nucl-ex
19
The categories of this paper are: eess
10
The categories of this paper are: q-bio
29
The categories of this paper are: funct-an
32
The categories of this paper are: atom-ph
13
The categories of this paper are: quant-ph
9
The categories of this paper are: nlin
20
The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
33
The categories of this paper are: plasm-ph
23
The categories of this paper are: solv-int
8
The categories of this paper are: hep-ex
36
The categories of this paper are: cmp-lg