Multiple caloric effects in geometrically frustrated “114” CaBaCo4O7 Cobaltite

Χ'(T) measurement shows two frequency independent magnetic transitions at 60 K and 66 K.Field induced metamagnetic transition is conformed in CBCO sample above the TC (60 K).AC susceptibility measurement shows frequency independent two magnetic transitions at 60 K and 66 K.

We have investigated the magnetocaloric and electrocaloric effects in “114” CaBaCo4O7 (CBCO) sample prepared by solid state method. Magnetization study has revealed the ferrimagnetic transition (TC) at 60 K and another transition at 66 K. Observation of irreversibility and first order nature of magnetic transition above TC has suggested a complicated magnetic nature of the system. A maximum magnetic entropy change of ~6.8 J/Kg-K has been found at TC and further a broadening of the entropy peak with the increase of magnetic field indicates the field induced transition above TC. From temperature dependent pyrocurrent measurements, we have measured the electric polarization under different electric fields and the change in isothermal electrocaloric entropy is found to be ~0.50 J-m−3 K−1 (for 150 kV/m) just above magnetic transition temperature.