Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Directed Transport in classical and quantum chaotic billiards   We construct an autonomous chaotic Hamiltonian ratchet as a channel billiard
subdivided by equidistant walls attached perpendicularly to one side of the
channel, leaving an opening on the opposite side. A static homogeneous magnetic
field penetrating the billiard breaks time-reversal invariance and renders the
classical motion partially chaotic. We show that the classical dynamics
exhibits directed transport, owing to the asymmetric distribution of regular
regions in phase space. The billiard is quantized by a numerical method based
on a finite-element algorithm combined with the Landau gauge and the Bloch
formalism for periodic potentials. We discuss features of the billiard
eigenstates such as node lines and vortices in the probability flow. Evidence
for directed quantum transport, inherited from the corresponding features of
the classical dynamics, is presented in terms of level-velocity statistics.

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The categories of this paper are: plasm-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: gr-qc
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The categories of this paper are: hep-ex
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The categories of this paper are: comp-gas
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The categories of this paper are: ao-sci
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The categories of this paper are: hep-th
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The categories of this paper are: cond-mat
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The categories of this paper are: cs
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The categories of this paper are: nucl-ex
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The categories of this paper are: funct-an
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The categories of this paper are: supr-con
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The categories of this paper are: q-alg
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The categories of this paper are: adap-org
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The categories of this paper are: astro-ph