Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: High harmonic interferometry of the Lorentz force in strong mid-infrared
  laser fields   The interaction of intense mid-infrared laser fields with atoms and molecules
leads to a range of new opportunities, from the production of bright, coherent
radiation in the soft x-ray range to imaging molecular structures and dynamics
with attosecond temporal and sub-angstrom spatial resolution. However, all
these effects, which rely on laser-driven recollision of an electron removed by
the strong laser field and the parent ion, suffer from the rapidly increasing
role of the magnetic field component of the driving pulse: the associated
Lorentz force pushes the electrons off course in their excursion and suppresses
all recollision-based processes, including high harmonic generation, elastic
and inelastic scattering. Here we show how the use of two non-collinear beams
with opposite circular polarizations produces a forwards ellipticity which can
be used to monitor, control, and cancel the effect of the Lorentz force. This
arrangement can thus be used to re-enable recollision-based phenomena in
regimes beyond the long-wavelength breakdown of the dipole approximation, and
it can be used to observe this breakdown in high-harmonic generation using
currently-available light sources.

32
The categories of this paper are: atom-ph
27
The categories of this paper are: comp-gas
20
The categories of this paper are: acc-phys
28
The categories of this paper are: alg-geom
4
The categories of this paper are: cond-mat
6
The categories of this paper are: astro-ph
26
The categories of this paper are: bayes-an
11
The categories of this paper are: hep-lat
15
The categories of this paper are: nucl-ex
2
The categories of this paper are: math
37
The categories of this paper are: supr-con
16
The categories of this paper are: stat
22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
30
The categories of this paper are: q-alg
29
The categories of this paper are: funct-an