Electric field control of magnetic properties of Nd2Fe14B thin films grown onto PMNPT substra.

Nd₂Fe₁₄B films with easy magnetization axis perpendicular to the film plane were grown onto Tabuffered piezoelectric (011)-0.7Pb(Mg_1/3Nb_2/3)O₃-0.3PbTiO₃ (PMN-PT) substrates using a magnetron sputtering technique. The film retains good permanent magnetic properties, with coercivities up to 1.4 T and spin reorientation near 150 K. Our investigations demonstrated that the converse piezoelectric effect generated by an electric field across the PMN-PT substrate can rotate the angle of spin reorientation of the Nd₂Fe₁₄B films, resulting in a considerable manipulation of magnetization by the electric field at temperatures below 150 K. The ratio of magnetization change reaches 30% in a magnetic field of 2 T when an electric field of 6 kV/cm is applied at 30 K. With increasing temperature, the electric field-induced tunability of magnetization decreases. These observations of permanent magnetic properties and electrically controlled magnetization effects make the Nd₂Fe₁₄B/PMN-PT heterostructure attractive for exploring multifunctional magnetic/electric devices. [ABSTRACT FROM AUTHOR]