(a) XRD intensity— pattern of thin film grown on /sapphire substrate. (b) EDAX of film.
(a) Room temperature characteristics of film at 100 kHz. The butterfly nature of curves suggests a weak ferroelectric behavior at room temperature. (b) Temperature dependence of magnetization of film is shown. The zero field cooled data are taken in the warming cycle with an external magnetic field of 0.1 T parallel to -axis. An AFM downturn is observed near 30 K. (c) Temperature dependence of resistivity at (●) and 3 T (▲). No trace of magnetoresistence is observed.
The loss factor as a function of temperature at 123 Hz is plotted. An inverse -shape anomaly is observed, which reflects the onset of AFM ordering in the system. Inset (a) shows and (b) shows dielectric constant as a function of temperature and magnetic field. The data are taken at 123 Hz and (◼), to -plane (●), and to -plane (▲).
Frequency and temperature dependence of . Symbols a–h represent data taken at 31, 53, 73, 123, 523, 1023, 5023, and 10023 Hz, respectively. At lowest frequency (31 Hz) the inverse anomaly is clearly evident. As we increase the frequency the magnitude of anomaly in decreases and at 10023 Hz the anomaly is barely visible. Inset shows the dielectric constant a function of temperature for a polycrystalline pellet in zero field and at 4 T magnetic field. The anomaly in dielectric constant corresponding to AFM transition is seen at .
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