On the structure of the superdiamagnetic state
Volkov B.A. , Kopaev Yu.V. , Nunuparov M.S. , Tugushev V.V.
The general form of gauge-invariant functional of free energy, valid for the ferromagnetic and superdiamagnetic cases, is shown. Using an example of the systems with electron-hole pairing, it is shown that the superdiamagnetic state can occur only as an inhomogeneous state. In particular, it can occur in the electron-type ferroelectrics in the region of domain walls.