Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spin filtering through a double-bend structure   We propose a simple scheme for the spin filter by studying the coherent
transport of electrons through a double-bend structure in a quantum wire with a
weak lateral magnetic potential which is much weaker than the Fermi energy of
the leads. {\em Extremely large} spin polarized current in the order of {\em
micro-Ampere} can be obtained because of the strong resonant behavior from the
double bends. Further study suggests the roubustness of this spin filter.

12
The categories of this paper are: nucl-th
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The categories of this paper are: hep-lat
18
The categories of this paper are: econ
20
The categories of this paper are: acc-phys
9
The categories of this paper are: nlin
24
The categories of this paper are: dg-ga
36
The categories of this paper are: cmp-lg
35
The categories of this paper are: mtrl-th
17
The categories of this paper are: q-fin
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph
14
The categories of this paper are: math-ph
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci
29
The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex