An one-dimensional model is suggested to simulate the tricritical phase transitions. The nonlinear excitations (solitary waves and kinks) which are the cluster walls are obtained. In the weak anharmonicity case the soft-mode behaviour takes place. It is shown that in the arbitrary anharmonicity case the soft-mode behaviour with full softening is only reached in the order-disorder regime. The domain wall energy and its thickness are calculated taking into account the nonuniform distribution of the polarization in a transition layer between the two domains with the directions of opposite signs of spontaneous polarization. The estimates of the energy and of the thickness are made for KH2PO4 crystals near the tricritical point. The results are compared with data which are available in literature.
|Number of pages||12|
|Journal||Physica B: Physics of Condensed Matter & C: Atomic, Molecular and Plasma Physics, Optics|
|State||Published - Nov 1983|
ASJC Scopus subject areas
- Engineering (all)