A thin film Co nanomagnet in the shape of an elongated hexagon has been inc
orporated in a vertical device structure consisting of the nanomagnet and a
thin Cu spacer layer formed on top of a thick Co film. The spin-polarized
current flowing between the nanomagnet and the Co film is used to abruptly
switch the magnetic alignment of the nanomagnet relative to that of the thi
ck Co layer by the transfer of spin angular momentum from the conduction el
ectrons to the nanomagnet moment. The shape anisotropy in the nanomagnet pr
omotes the single domain behavior required for nonvolatile memory applicati
ons. (C) 2000 American Institute of Physics. [S0003-6951(00)04549-6].