Continuous Tuning of W-doped VO2 Optical Properties for Terahertz Analog Applications
Date
2014-11-17
Authors
Karaoglan-Bebek, Gulten
Hoque, M. N. F.
Holtz, Mark
Fan, Zhaoyang
Bernussi, Ayrton
Journal Title
Journal ISSN
Volume Title
Publisher
American Institute of Physics
Abstract
Vanadium dioxide (VO2), with its characteristic metal-insulator phase transition, is a prospective active candidate to realize tunable optical devices operating at terahertz (THz) frequencies. However, the abrupt phase transition restricts its practical use in analog-like continuous applications. Incorporation of tungsten is a feasible approach to alter the phase transition properties of thin VO2 films. We show that amplitude THz modulation depth of ~65%, characteristic phase transition temperature of ~40 0C, and tuning range larger than 35 0C can be achieved with W-doped VO2 films grown on sapphire substrates. W-doped VO2 films can also be used to suppress Fabry-Perot resonances at THz frequencies but at temperatures much lower than that observed for undoped VO2 films. The gradual phase transition temperature window allows for precise control of the W-doped VO2 optical properties for future analog based THz devices.
Description
Keywords
vanadium dioxide, transition metals, optical resonators, optical devices, phase transitions, optical properties, frequency spectrum, Physics
Citation
Karaoglan-Bebek, G., Hoque, M. N. F., Holtz, M., Fan, Z., & Bernussi, A. A. (2014). Continuous tuning of W-doped VO2 optical properties for terahertz analog applications. Applied Physics Letters, 105(20).