Abstracts Book - IMRC 2018

• SC2-O010 Invited Talk
PULSED LASER DEPOSITION OF METAL-INSULATOR TRANSITION
MATERIALS
Mohamed Chaker 1
1 Institut National de la Recherche Scientifique, Université du Québec, Energy Materials
Telecommunications, Canada.
We focus on the synthesis of metal-insulator transition (IMT) materials using the
Pulsed Laser Deposition (PLD) technique that allows an excellent control of
material stoichiometry and density as well as of the material nanostructure.
Vanadium dioxide (VO2) and samarium nickelate (SmNiO3) are particularly
interesting IMT materials as their electrical resistivity as well as their infrared
and terahertz (THz) reflectivity undergo significant changes across the
thermo/photo-induced IMT, at transition temperatures TIMT ≈ 68 °C and 130 °C
respectively. In a series of investigations, our group has examined the physics
governing the IMT of VO2 and SmNiO3 thin films and has explored application
opportunities including uncooled bolometers, and smart radiator devices for
space applications.
We overview our recent studies related to understanding and exploiting the MIT
of VO2 and SmNiO3 for various applications. First, we report on the design and
fabrication of a new type of high-performance variable-emittance smart coating
based on VO2 thin films. This smart coating passively switches from low
emittance at low temperature to high emittance at high temperature, which
offers a great potential for smart radiator devices in microsatellites. Second, we
present a multilayer structure (MLS) based on tungsten-doped VO2 films that
displays a combination of excellent characteristics (i.e. large thermal coefficient
of resistance, low resistivity and small hysteresis width) suitable for the
development of sensing layers for the next generation of high-performance
uncooled microbolometers. Finally, we show that PLD can be used to grow on
SrTiO3 epitaxial SmNiO3 films with good MIT characteristics in the mid-infrared
region. The influence of the in-plane tensile strain on the structure and on the
electrical and infrared optical properties of these films is also discussed.
Keywords: Thin films, Metal-insulator transition materials, Vanadium dioxide and
samarium nickelate
Presenting authors email: chaker@emt.inrs.ca