Phase Separation And Metastability Across First Order Transition.

      Аннотация: Magnetic material which shows first order magnetic transition has been of interest due to their functional properties like giant magnetocaloric effect, giant magnetoresistance, giant magnetostriction, etc. Many of these functional magnetic materials are multi-component systems whose properties become more interesting under substitution. Such substitutions are an intrinsic source of frozen disorder which leads to broadening of first order transition. In this work role of chemical disorder has been studied in such a functional intermetallic systems. Bulk measurement on these materials shows some anomalous feature at low temperature which were explained in terms of "kinetic arrest" and compared with mangenites materials. This work gives a microscopic evidence of phase separation and way to find out the difference between thermomagnetic irreversibility appear in different temperature region. This work also gives an idea about variation in features related with FOMPT like transition width and hysteresis width under extream conditions like high pressure and high magnetic field.

Ключевые слова: GMR, phase transition, metastability, Phase coexistance, Thermomagnetic Irrversibility, Functional material