1. A nonvolatile memory element, comprising: a first electrode layer and a second electrode layer; a first variable resistance layer disposed between the first electrode layer and the second electrode layer, wherein the first variable resistance layer comprises a first material that comprises a first chemical element and a second chemical element; and a first layer disposed on the first variable resistance layer, and comprising a second material that comprises the first chemical element and the second chemical element, wherein a ratio of the first chemical element to the second chemical element in the first layer is non-stoichiometric.