A multilayer structure is disclosed that includes a conductive layer, a layer of a negative differential resistance (NDR) material disposed above the conductive layer, a layer M2 disposed above the NDR material, a second layer of NDR material disposed above layer M2, and a conductive layer disposed above the second NDR layer. Layer M2 can include a conductive material interspersed with regions of a dielectric material or a layer of the dielectric material and regions of the conductive material disposed above and below the dielectric material.