Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: $SU(2) \otimes SU(2)$ bi-spinor structure entanglement induced by a step
  potential barrier scattering in two-dimensions   The entanglement between $SU(2) \otimes SU(2)$ internal degrees of freedom of
parity and helicity for reflected and transmitted waves of Dirac-like particles
scattered by a potential step along an arbitrary direction on the $x-y$ plane
is quantified. Diffusion ($E \geq V$) and Klein zone ($V \geq E$) energy
regimes are considered. It has been shown that, for $SU(2) \otimes SU(2)$
polarized structures of helicity eigenstates impinging the barrier, the local
interaction with a {\em step} potential destroys the {\em parity-spin}
separability. The framework presented here can be straightforwardly translated
into a useful theoretical tool for obtaining the {\em spin-spin} entanglement
in the context of enlarged scenarios of nonrelativistic $2D$ systems, as for
instance those for describing single layer graphene, or even single trapped
ions with Dirac bi-spinor mathematical structure.

1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph
12
The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
32
The categories of this paper are: atom-ph
27
The categories of this paper are: comp-gas
5
The categories of this paper are: gr-qc
26
The categories of this paper are: bayes-an
33
The categories of this paper are: plasm-ph
19
The categories of this paper are: eess
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The categories of this paper are: math
23
The categories of this paper are: solv-int
10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con