The present invention is directed to a memory cell including first and second unidirectional selectors coupled in parallel to a nonvolatile memory element. Each of the first and second unidirectional selectors includes first, second, and third electrode layers; a first insulator layer interposed between the first and second electrode layers; and a second insulator layer interposed between the second and third electrode layers. The first insulator layer of the first unidirectional selector includes therein a permanent conductive path and the second insulator layer of the first unidirectional selector is operable to form therein a volatile conductive path upon application of a potential across the first unidirectional selector. The second insulator layer of the second unidirectional selector includes therein another permanent conductive path and the first insulator layer of the second unidirectional selector is operable to form therein another volatile conductive path upon application of another potential across the second selector.