Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Near-field imaging of dipole emission modulated by an optical grating   Multiphoton-ionized electrons are born into a strong light field that will
determine their short-term future. By controlling the infrared beam, we enable
atoms or molecules to generate extreme ultraviolet (XUV) pulses and synthesize
attosecond pulses - the shortest controlled events ever produced. Here we show
that a weak obliquely incident beam imposes an optical grating on the
fundamental beam, resulting in a spatially modulated attosecond pulse. We
observe the modulation on a spectrally resolved near-field XUV image, encoding
all information of the spectral phase of the recollision electron and,
therefore, the attosecond pulse produced by structureless atoms. Near-field
imaging is an efficient method for measuring the duration of attosecond pulses,
especially important for soft X-ray pulses created in helium. For more complex
systems, it includes auto ionization and giant plasmon resonances.

11
The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
16
The categories of this paper are: stat
13
The categories of this paper are: quant-ph
17
The categories of this paper are: q-fin
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg
15
The categories of this paper are: nucl-ex
23
The categories of this paper are: solv-int
29
The categories of this paper are: funct-an
4
The categories of this paper are: cond-mat
28
The categories of this paper are: alg-geom