The Rayleigh law describes the behavior of ferromagnetic materials at low fields.
Ferromagnetic materials consist of magnetic domains. When a small external field
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The Rayleigh law was derived theoretically by Louis Néel.,
The same law describes polarization and direct and converse piezoelectric response of some ferroelectric and ferroelectric-ferroelastic materials. The common feature for ferromagnetic, ferroelectric and ferroelastic materials (i.e., ferroic materials) are domains whose boundaries (domain walls) can be moved by magnetic, electric or mechanical fields.