Spin engineering of CoPd alloy films via the inverse piezoelectric effect

The spin engineering of CoxPd1-x alloy films on Pb(Zr0.52Ti0.48)O-3 substrates was studied by measuring the polar Kerr rotation hysteresis loops and their electric field dependencies. The electric field dependence of polar Kerr rotation strongly depends on the composition of the CoPd alloys. This is especially so in the case of Co0.25Pd0.75 alloy film where the hysteresis loop of magnetic remanence with respect to voltage applied is nearly squared, i.e., the direction of magnetization maintains its initial state even when the voltage applied is turned off. This spin engineering in a ferromagnetic/piezoelectric hybrid system is possible mainly due to a combination of the magnetostrictive effect and the inverse piezoelectric effect. The results are applicable to future nonvolatile memory devices. (C) 2003 American Institute of Physics.