English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The Bruggeman homogenization formalism was used to numerically investigatethe dielectric properties of a columnar thin film (CTF) made from vanadiumdioxide. For visible and near-infrared wavelengths, the CTF iselectromagnetically equivalent to a homogeneous orthorhombic material. Over the58 deg C -- 72 deg C temperature range, the eigenvalues of the CTF's relativepermittivity dyadic are highly sensitive to temperature, and vary according towhether the CTF is being heated or cooled. The anisotropy revealed through theeigenvalues, and the anisotropy of the associated hysteresis, were investigatedin relation to temperature for CTFs of different porosities and columnar crosssections. When the free-space wavelength is 800 nm, the CTF is a dissipativedielectric material that exhibits temperature-dependent anisotropy andanisotropic hysteresis. In contrast, when the free-space wavelength is 1550 nm,the CTF can be either a dissipative dielectric material, a hyperbolic materialor a metal-like material, depending on the temperature and the porosity of theCTF. As the porosity of the CTF decreases from 0.55 to 0.3, the anisotropy ofthe CTF becomes more pronounced, as does the anisotropy of the hysteresis. Onlyrelatively modest variations in anisotropy and hysteresis arise in response tovarying the columnar cross-sectional shape, as compared to the variationsinduced by varying the porosity.

Towards Morphologically Induced Anisotropy in Thermally Hysteretic Dielectric Properties of Vanadium Dioxide