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Static negative susceptibility in ferromagnetic material induced by domain wall motion: an aspect of superconductor state

Domain wall motion in magnetic materiel induces the negative susceptibility leading to a perfect diamagnetism state. The local susceptibility is calculated by the derivative of magnetization ($\vec{M}$) vector w.r.t. magnetic field strength ($\vec{H}$) vector. In the transient region from the upward domain to the downward domain (domain wall width), local $\vec{M}$ and $\vec{H}$ vectors exhibit opposite slopes, which leads to a negative susceptibility value. A negative susceptibility value induces the diamagnetism effect leading to a relative permeability value $<$ 1 $\left(μ_r < 1\right)$. This diamagnetism sate originates due to the domain wall motion, which is an entirely different mechanism from the electron motion&#39;s induced diamagnetism. Furthermore, the strength of the diamagnetism state can be enhanced by tuning the gradient energy of a domain that may correspond to a perfect diamagnetism state $\left(χ_v \approx -1 \Rightarrow μ_r \rightarrow 0\right)$. Besides, we believe that there may be a possibility of sustaining such a diamagnetic state (domain wall induced) in a ferromagnetic material that is utterly contradictory to the conventional theory.