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arXiv · 1512.08888

Pyroelectric Control of Spin Polarization Assisted Coexistence of Giant Positive and Negative Magnetocaloric Effects

Gaurav Vats·Ashok Kumar·Ram S. Katiyar·Nora Ortega
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Abstract

Electric field control of magnetism is the key to many next generation spintronics applications1. Ferroelectric control of spin polarization2,3 followed by the electrically driven repeatable magnetization reversal in the absence of applied magnetic field4 have proven to be the milestones in this direction. This article propose how these phenomena could be utilized in a reverse manner to gain control over magnetization even in the absence of electric field. In turn, coexistence of positive5 as well as negative6 magnetocaloric effect (MCE) is attained in tri-layered PbZr0.53Ti0.47O3-CoFe2O4-PbZr0.53Ti0.47O3 (PZT/CFO/PZT) nanostructures for identical temperature ranges when subjected to different applied magnetic fields. Unlike conventional approaches5-9 the present study demonstrate that it is possible to obtain giant MCE merely by magneto-pyroelectric coupling. Consequently, the MCE entropy changes calculated using Maxwell equations are found to be as large as reported for existing giant MCE values6,9,10.

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Gaurav Vats, Ashok Kumar, Ram S. Katiyar, Nora Ortega. 2015-12-30. Pyroelectric Control of Spin Polarization Assisted Coexistence of Giant Positive and Negative Magnetocaloric Effects. https://arxiv.org/abs/1512.08888

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