Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Experimental Observation of Partial Parity-Time Symmetry and Its Phase
  Transition with a Laser-Driven Cesium Atomic Gas   Realization and manipulation of parity-time (PT) symmetry in multidimensional
systems are highly desirable for exploring nontrivial physics and uncovering
exotic phenomena in non-Hermitian systems. Here, we report the first
experimental observation of partial PT (pPT) symmetry in a cesium atomic gas
coupled with laser fields, where a two-dimensional pPT-symmetric optical
potential for probe laser beam is created. A transition of the pPT symmetry
from an unbroken phase to a broken one is observed through changing the
beam-waist ratio of the control and probe laser beams, and the domains of
unbroken, broken, and non-pPT phases are also discriminated unambiguously.
Moreover, we develop a technique to precisely determine the location of the
exceptional point of the pPT symmetry breaking by measuring the asymmetry
degree of the probe-beam intensity distribution. The findings reported here
pave the way for controlling multidimensional laser beams in non-Hermitian
systems via laser-induced atomic coherence, and have potential applications for
designing new types of light amplifiers and attenuators

18
The categories of this paper are: econ
27
The categories of this paper are: comp-gas
6
The categories of this paper are: astro-ph
23
The categories of this paper are: solv-int
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
9
The categories of this paper are: nlin
31
The categories of this paper are: ao-sci
13
The categories of this paper are: quant-ph
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The categories of this paper are: hep-lat
22
The categories of this paper are: chao-dyn
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The categories of this paper are: atom-ph
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The categories of this paper are: alg-geom