RuVO2 alloy epitaxial films: Lowered insulator–metal transition temperature and retained modulation capacity

Alloying VO2 by Ru incorporation (RuxV1−xO2) should decrease the insulator–metal-transition (IMT) temperature due to the unique semi-metallic properties of RuO2. We deposit high-quality RuxV1−xO2 thin films by pulsed laser deposition on (0001) sapphire substrates. We investigate the structural, electrical, and optical properties of the RuxV1−xO2 alloy films using x-ray diffraction, x-ray photoelectron spectroscopy, UV-Vis–NIR spectrophotometry, and four-point-probe resistivity measurements. Our results confirm that Ru alloying of VO2 reduces effectively the IMT temperature while retaining the IMT characteristics of the material.