Heterostructures that include a bilayer composed of epitaxial layers of vanadium dioxide having different rutile-to-monoclinic phase transition temperatures are provided. Also provided are electrical switches that incorporate the heterostructures. The bilayers are characterized in that they undergo a single-step, collective, metal-insulator transition at an electronic transition temperature. At temperatures below the electronic transition temperature, the layer of vanadium dioxide having the higher rutile-to-monoclinic phase transition temperature has an insulating monoclinic crystalline phase, which is converted to a metallic monoclinic crystalline phase at temperatures above the electronic transition temperature.