Anomalous coercivity enhancement with temperature and tunable exchange bias in Gd and Ti co-doped BiFeO3 multiferroics

作者：Ahmmad Bashir^*; Islam M Z; Billah Areef; Basith M A^*

来源：Journal of Physics D: Applied Physics , 2016, 49(9): 095001.

DOI：10.1088/0022-3727/49/9/095001

• magnetism
• multiferroics
• coercivity
• exchange bias

We have investigated the effects of temperature on the magnetic properties of the Bi0.9Gd0.1Fe1-xTixO3 (x = 0.00-0.20) multiferroic system. Unexpectedly, the coercive fields (H-c) of this multiferroic system increased with increasing temperature. The coercive fields and remanent magnetization were higher over a wide range of temperatures in sample x = 0.10, i.e. in a sample with a composition Bi0.9Gd0.1Fe0.9Ti0.1O3 than those of x = 0.00 and 0.20 compositions. Therefore, we carried out temperature-dependent magnetization experiments extensively for sample x = 0.10. The magnetic hysteresis loops at different temperatures exhibit an asymmetric shift towards the magnetic field axes, which indicates the presence of an exchange bias effect in this material system. The hysteresis loops were also carried out at temperatures of 150 K and 250 K by cooling down the sample from 300 K in various cooling magnetic fields (H-cool). The exchange bias field (H-EB) values increased with H-cool and decreased with temperature. The H-EB values were tunable by field cooling at temperatures of up to 250 K.

• 出版日期2016-3-9