Exchange bias effect in multiferroic Eu0.75Y0.25MnO3

The exchange bias phenomenon has been investigated in multiferroic Eu0.75Y0.25MnO3. The material shows a weak ferromagnetism with cone spin configuration induced by external magnetic field below 30 K. Consequently, the electric polarization coming from the cycloid spin order below 30 K can be suppressed by external magnetic fields. The magnetic hysteresis loops after cooling in a magnetic field exhibit characteristics of exchange bias below the spin glassy freezing temperature (Tg)∼16 K. The exchange bias field, coercivity field, and remanent magnetization increase with increasing cooling magnetic field. The exchange bias effect is ascribed to the frozen uncompensated spins at the antiferromagnetism/weak ferromagnetism interfaces in the spin-glass like phase.

► Exchange bias phenomenon has been investigated in multiferroic Eu0.75Y0.25MnO3.
► A weak ferromagnetism with cone spin configuration is induced by an external magnetic field.
► Exchange bias is below the spin glassy freezing temperature (Tg)∼16 K.
► The exchange bias field increases with increasing cooling magnetic field.
► There are frozen uncompensated spins at the anti-ferromagnetism (FM)/weak FM interfaces.