Dmitri Tenne and recent physics graduate Joseph Spinuzzi, now a graduate student at the University of California-Merced, are co-authors of a research paper titled “Isostructural metal-insulator transition in VO2,” which has been published in a recent issue of the top-ranked research journal, Science.
Here is a brief description of their work: Bulk vanadium dioxide (VO2) is a metal above 68 degrees Celsius, but transforms into an insulator when cooled below that temperature. This transition is usually coupled to a symmetry lowering change of crystal structure. The duo’s research showed that in a specially designed thin film heterostructure consisting of a layer of VO2 and a layer of the same material with a little oxygen deficiency, these transitions can be decoupled, and a new metallic monoclinic phase of vanadium oxide appears.
Raman spectroscopy experiments of Spinuzzi and Tenne provided key evidence for this new phase of VO2. This discovery will provide insights into phase transitions of correlated materials and may aid the design of device functionalities.