In previous papers, the authors have ab initio constructed a nonempirical pair interatomic potential of rare-gas crystals. It was constructed for the case of high pressures (strong compression). The equations of state are solved and the elastic constants responsible for the propagation of sound in strongly compressed crystals of rare gases are calculated in the next-nearest-neighbor approximation using the interatomic potential proposed by the authors. The results of calculations are in satisfactory agreement with the experimental data. The shear modulus B 12 is described somewhat less well. The last experiment data show that Cauchy relation is satisfied in krypton consequently the interatomic interaction in the rare-gas crystals has a central character.

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Complete magnetization and magnetostriction loops for type II superconductors were calculated in terms of the following pinned critical state models which incorporate the flux jump instability criterion: the Kim–Anderson model, the exponential model, the linear model, and the model with peak effect. These results were used for constructing magnetic field–temperature (H–T) diagrams of instability of these critical state models. Magnetothermal instabilities of superconductors with peak effect were investigated experimentally and theoretically. Regions in the H–T diagram where flux jumps occur were built and compared with experimental M(H) hysteresis loops. We have explained the phenomenon of “island” jumps. The influence of flux trapping on the flux jump regions of magnetic fields was studied.

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We have studied magnetothermal instabilities both theoretically and experimentally. Magnetostriction and magnetization hysteresis loops with flux jumps were calculated over a wide range of experimental parameters employing three critical state models: the original Bean model, the Kim–Anderson model, and the exponential model. The influence of the magnetic prehistory on the flux jumps, magnetostriction, and the magnetization was investigated for the LaSrCuO crystal. H–T diagrams of flux instabilities were constructed from calculation and from experimental results. One can see good qualitative agreement between these two diagrams.

We have studied magnetothermal instabilities, giant flux jumps, both theoretically and experimentally. Magnetostriction and magnetization hysteresis loops with flux jumps were calculated over a wide range of experimental parameters employing two critical-state models: the Kim-Anderson model and the exponential model. The influence of the magnetic history on the flux jumps' magnetostriction and magnetization were investigated for the LaSrCuO single crystal. The shape of the unstable region of the critical state in the temperature-magnetic field plane was constructed from calculations and experimental results. In the Kim-Anderson model H-T diagrams of flux instabilities agree well with experimental results on HTSC single-crystal LaSrCuO and experimental results on LTSC niobium.

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