Effect of Interfaces on the Magnetoelectric Properties of Co/PZT/Co Heterostructures

摘要

We have studied Co (film)/PZT (substrate)/Co (film) heterostructures with plane-parallel interfaces, produced by direct growth of cobalt films 0.5 to 3.5 μm thick on PZT surfaces smoothed to a subnanometer level (where PZT stands for a ceramic PbZr_(0.45)Ti_(0.55)O_3 lead zirconate titanate ferroelectric substrate). The results demonstrate that they possess magnetoelectric properties comparable in magnitude to those characteristic of known structures but, in contrast to these latter, allow one to dispense with the condition that the volume fractions of the ferromagnetic and ferroelectric components be roughly equal. The interface is shown to play a key role in determining the magnetoelectric response of the heterostructures: above 9 mV/(cm Oe) (11.7 mV/A) in a magnetic field of 50 Oe (3980 A/m) at a frequency of 100 Hz and room temperature. The heterostructures are potentially attractive for use as nonvolatile sensors in household devices.