A device configured to have a nanowire formed laterally between two electrodes includes a substrate and an insulator layer established on at least a portion of the substrate. An electrode of a first conductivity type and an electrode of a second conductivity type different than the first conductivity type are established at least on the insulator layer. The electrodes are electrically isolated from each other. The electrode of the first conductivity type has a vertical sidewall that faces a vertical sidewall of the electrode of the second conductivity type, whereby a gap is located between the two vertical sidewalls. Methods are also disclosed for forming the device.