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Updated: Jun 21, 2026

Atomic Layer Deposition of Vanadium Dioxide and a Temperature-dependent Optical Model
Published on: May 23, 2018
In situ study of the metal-insulator transition in VO2 by EELS and ab initio calculations
F Espinosa-Magaña1, Alberto Rosas, H E Esparza-Ponce
1Centro de Investigación en Materiales Avanzados, S.C., Laboratorio Nacional de Nanotecnología, Miguel de Cervantes 120, Complejo Industrial Chihuahua, 31109 Chihuahua, Chihuahua, Mexico. francisco.espinosa@cimav.edu.mx
Abstract:
Changes in the dielectric properties during the thermochromic transition of commercial VO(2) powders were determined in situ, by analyzing the low-loss region of the electron energy-loss spectroscopy (EELS) spectra in a transmission electron microscope at room temperature (insulator phase) and 100 degrees C (metallic phase). A comparison of experimental EELS spectra and ab initio density-functional theory calculations (WIEN2k code) within the generalized gradient approximation (GGA) is presented. A characteristic peak around 5.6 eV appears in the energy-loss function in metallic phase, which is absent in insulator phase. The origin of the characteristic peak is analyzed by means of energy-band structure calculations.
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