(1) Institute of Physics, Dagestan Scientific Center, Russian Academy of Sciences, ul. 26 Bakinskikh komissarov 94, Makhachkala, 367003, Russia;(2) Lomonosov Moscow State University, Leninskie gory, Moscow, 119992, Russia
Abstract:
The heat capacity of the La0.9Ag0.1MnO3 manganite is measured in the temperature range 77–350 K and studied in detail in the vicinity of the Curie temperature for the first time. The regularities of the variation in the universal critical parameters in the vicinity of the phase transition point are established. The critical exponent and the amplitude of the heat capacity are calculated to be α = ?0.127 and A+/A? = 1.146 with due regard for the scaling corrections. These parameters correspond to the critical behavior within the three-dimensional Heisenberg model. The size of ferromagnetic droplets in the paramagnetic range at T > TC is estimated as ξ ≈ 19 Å. The results obtained are analyzed thoroughly and compared with theoretical data for a number of model systems.