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تسجيل مستخدم جديدBarkhausen-type noise in the resistance of antiferromagnetic Cr thin films
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We present an experimental study of the changes generated on the electrical resistance $R(T)$ of epitaxial Cr thin films by the transformation of quantized spin density wave domains as the temperature is changed. A characteristic resistance noise appears only within the same temperature region where a cooling-warming cycle in $R(T)$ displays hysteretic behavior. We propose an analysis based on an analogy with the Barkhausen noise seen in ferromagnets. There fluctuations in the magnetization $M(H)$ occur when the magnetic field $H$ is swept. By mapping $M rightarrow Psi_0$ and $H rightarrow T$, where $Psi_0$ corresponds to the order parameter of the spin density wave, we generalize the Preisach model in terms of a random distribution of {it resistive hysterons} to explain our results. These hysterons are related to distributions of quantized spin density wave domains with different sizes, local energies and number of nodes.
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