A special type of condensed medium is the medium with magnetic order.
Hamiltonian of the interaction between an electron and the magnetoordered crystal has the
- are s-d(f) exchange and
Heisenberg Hamiltonians, respectively.
It is shown in
that as distinct from the polaron in the ionic crystal, the electron
interacts with magnetic atom spins at a short range and electron self-localized states
are separated from delocalized ones by a potential barrier. The electron capture would
thus be expected to be of activation character ехр(-А/КТ)
new types of electron localized states separated from each other by a potential barrier
were found in antiferromagnetics with coulomb impurity. It was shown, that under the
influence of an external magnetic field the electron may change from one state into
the other. These results can be used in explaining conductive properties of magnetic
a new type of self-localized states in antiferromagnetics in a quantizing magnetic field
is found, such that a particle can transfer into these states without overcoming the
potential barrier. These are self-consistent states of an electron and a soliton-type
magnetization distribution (Fig.1), extended in shape along the magnetic field direction.
These states are responsible for optical and electric properties of antiferromagnetic
semiconductors in a strong magnetic field. They may also be vital in oxide ceramics,
where the high-temperature superconductive phase coexists with the antiferromagnetic one.
Fig.1. Schematic representation of the region, where electron is self-localized
in antiferromagnetic without overcoming a potential barrier