Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Atomic spin-wave control and spin-dependent kicks with shaped
  subnanosecond pulses   The absorption of traveling photons resonant with electric dipole transitions
of an atomic gas naturally leads to electric dipole spin wave excitations. For
a number of applications, it would be highly desirable to shape and coherently
control the spatial waveform of the spin waves before spontaneous emission can
occur. This paper details a recently developed optical control technique to
achieve this goal, where counter-propagating, shaped sub-nanosecond pulses
impart sub-wavelength geometric phases to the spin waves by cyclically driving
an auxiliary transition. In particular, we apply this technique to reversibly
shift the wave vector of a spin wave on the $D2$ line of laser-cooled $^{87}$Rb
atoms, by driving an auxiliary $D1$ transition with shape-optimized pulses, so
as to shut off and recall superradiance on demand. We investigate a
spin-dependent momentum transfer during the spin-wave control process, which
leads to a transient optical force as large as $\sim 1\hbar k$/ns, and study
the limitations to the achieved $70\sim 75\%$ spin wave control efficiency by
jointly characterizing the spin-wave control and matterwave acceleration. Aided
by numerical modeling, we project potential future improvements of the control
fidelity to the $99\%$ level when the atomic states are better prepared and by
equipping a faster and more powerful pulse shaper. Our technique also enables a
background-free measurement of the superradiant emission to unveil the precise
scaling of the emission intensity and decay rate with optical depth.

21
The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
35
The categories of this paper are: mtrl-th
7
The categories of this paper are: hep-th
20
The categories of this paper are: acc-phys
6
The categories of this paper are: astro-ph
31
The categories of this paper are: ao-sci
24
The categories of this paper are: dg-ga
12
The categories of this paper are: nucl-th
25
The categories of this paper are: patt-sol
33
The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin
13
The categories of this paper are: quant-ph
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
32
The categories of this paper are: atom-ph