1. A ferroelectric tunneling element comprising: a thin film layer of ferroelectric material and a pair of electrically-conductive layers disposed on opposite sides of the ferroelectric layer, one of the conductive layers being dissimilar to the other of the conductive layers in composition or construction so that when the tunneling element is below the Curie temperature of the layer of ferroelectric material, the transport behavior of the conductive layers is polarization dependent.