Аннотация
Motivated by recent experimental observations on ultrathin Fe/Cu(001) films,
we performed a theoretical analysis of magnetic domain pattern evolution in 2D
Dipolar Frustrated Ising Ferromangnet.
Patterns -of oppositely magnetized regions- arise from the
competition between long-ranged dipolar interaction and nearest neighbor
ferromagnetic exchange interaction. One well established experimental result is
the domain size reduction with the
increasing of the temperature, independently of the
underlying pattern.
For the ideal stripe pattern and under the
Mean Field approximation, we found that the domain width ($h(T)$) decreases
while the temperature is increased from $T=0$ to the Curie temperature ($T_C$);
the two well known limits of $h$ for $T=0$ and $T_C$
are recovered continuously together with the expected shape of modulation
(squared and cosine wave respectively).
The lack of translational invariance,
intrinsic in the pattern, implies that thermal
fluctuations finally favor the dipolar interaction in
its competition with the exchange interaction; this is the driving
mechanism for domain shrinking, which is accompanied by
the occurrence of a non-trivial magnetization
profile at intermediate temperatures.
Preliminary Monte Carlo results will be also discussed.
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