A negative index material (or metamaterial) crossbar includes a first layer of approximately parallel nanowires and a second layer of approximately parallel nanowires that overlay the nanowires in the first layer. The nanowires in the first layer are approximately perpendicular in orientation to the nanowires in the second layer. Each nanowire of the first layer and each nanowire of the second layer has substantially regularly spaced fingers. The crossbar further includes resonant elements at nanowire intersections between the respective layers. Each resonant element includes two fingers of a nanowire in the first layer and two fingers of a nanowire in the second layer.