Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Current-induced magnetic superstructures in exchange-spring devices   We investigate the potential to use a magneto-thermo-electric instability
that may be induced in a mesoscopic magnetic multi-layer (F/f/F) to create and
control magnetic superstructures. In the studied multilayer two strongly
ferromagnetic layers (F) are coupled through a weakly ferromagnetic spacer (f)
by an "exchange spring" with a temperature dependent "spring constant" that can
be varied by Joule heating caused by an electrical dc current. We show that in
the current-in-plane (CIP) configuration a distribution of the magnetization,
which is homogeneous in the direction of the current flow, is unstable in the
presence of an external magnetic field if the length L of the sample in this
direction exceeds some critical value Lc ~ 10 \mu m. This spatial instability
results in the spontaneous formation of a moving domain of magnetization
directions, the length of which can be controlled by the bias voltage in the
limit L >> Lc. Furthermore, we show that in such a situation the
current-voltage characteristics has a plateau with hysteresis loops at its ends
and demonstrate that if biased in the plateau region the studied device
functions as an exponentially precise current stabilizer.

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The categories of this paper are: astro-ph
11
The categories of this paper are: hep-lat
31
The categories of this paper are: ao-sci
29
The categories of this paper are: funct-an
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The categories of this paper are: eess
14
The categories of this paper are: math-ph
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
30
The categories of this paper are: q-alg
22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex
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The categories of this paper are: math
33
The categories of this paper are: plasm-ph
10
The categories of this paper are: q-bio