Nanotube-based switching elements and logic circuits. Under one aspect, a switching element includes an input node; an output node; a nanotube channel element comprising a ribbon of nanotube fabric; and a control electrode disposed in relation to the nanotube channel element to form an electrically conductive channel between the input node and the output node, wherein the electrically conductive channel at least includes the nanotube channel element. Under another aspect, a switching element includes an input node; an output node; a nanotube channel element comprising at least one electrically conductive nanotube, the nanotube being clamped at both ends by a clamping structure; and a control electrode disposed in relation to the nanotube channel element to form an electrically conductive channel between the input node and the output node, wherein the electrically conductive channel at least includes the nanotube channel element.