Spin dependent tunneling devices with magnetization states based on stress conditions

摘要

A spin dependent tunneling device includes an electrically insulative material intermediate layer, a magnetization reference layer on one of the opposite major surfaces of the intermediate layer, and a memory film of a magnetostrictive, anisotropic ferromagnetic material on the other of the opposite major surfaces of the intermediate layer. The memory film material has a magnetization directed at an angle with respect to the relatively fixed direction of the magnetization reference layer, due to an effective magnetic bias field being present, in a first kind of stress condition with unequal coercivities for external magnetic fields applied in opposite directions. In one kind of stress condition the device has a coercivity with a magnitude exceeding that of the effective magnetic bias field, and in another kind of stress condition, the device has a coercivity with a magnitude less than that of the effective magnetic bias field.