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Register a new userMetamagnetic behavior and effect of field cooling on sharp magnetization jumps in multiferroic Y2CoMnO6
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We present sharp magnetization jumps and field induced irreversibility in magnetization in multiferroic Y2CoMnO6. Appearance of magnetic relaxation and field sweep rate dependence of magnetization jumps resemble the martensite like scenario and suggests the coexistence of E*-type antiferromagnetic and ferromagnetic phases at low temperatures. In Y2CoMnO6, the critical field required for the sharp jump can be increased or decreased depening on the magnitude and direction of the cooling field; this is remarkably different from manganites or other metamagnetic materials where the critical field increases irrespective of the direction of the field cooling. The cooling field dependence on the sharp magnetization jumps has been described by considering exchange pinning mechanism at the interface, like in exchange bias model.
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We have investigated multiple caloric effects in multiferroic Y2CoMnO6. Polycrystalline sample prepared by solid state method has shown a ferromagnetic Curie temperature 75 K with second order phase transition; a maximum magneto entropy change -$Delta$S_{Mmax}) of ~ 7.3 J/kg K with reasonable relative cooling power 220 J/kg is found without thermal and magnetic hysteresis loss. Electric field driven entropy change (-$Delta$S_{Emax}) of ~ 0.26 J/m^3 K obtained using the Maxwells relation and estimated magnetically induced total temperature change of 5.45 K around Curie temperature that confirms the multicaloric effect in the sample.
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