Analysis of critical behaviour of gyrotropy at phase transitions in crystals

Authors

  • О. С. Кушнір Ivan Franko Lviv National University, Ukraine
  • Р. Я. Шопа Ivan Franko Lviv National University, Ukraine

DOI:

https://doi.org/10.24144/2415-8038.2003.14.142-148

Abstract

On the basis of experimental data for the optical activity in Рb5(Ge1.хSix)3O11, (Рb1-xВах)5Ge3О11 and (NН3С3Н7)2МnСl4 crystals, the influence of order parameter fluctuations appearing in the course of phase transitions on the optical properties of these crystals is analyzed. An approach is used which is based on introducing a socalled first fluctuation correction into the Landau theory. Quantitative parameters of the chosen model are calculated. The results of the analysis testify a possibility for application of the model for describing the critical behaviour for the proper ferroelectric and incommensurately modulated phase transitions.

References

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Published

2003-12-25

Issue

Vol. 14 (2003)

Section

Статті

License

Copyright (c) 2003 Scientific Herald of Uzhhorod University.Series Physics

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