Optical properties of cubic hafnia stabilized with yttria

Abstract

The composition, transparency, refractive index, and infrared reflectance of yttria-stabilized cubic hafnia (c-HfO(2)) single crystals were measured. The material is transparent from the ultraviolet to the mid-infrared and for 9.6-mol % Y(2)O(3), the index is slightly smaller than for comparable cubic zirconia c-ZrO(2) or for diamond, but the dispersion (n(F) - n(c) = 0.02811) is larger than that of diamond. The index vs wavelength from 0.36 microm in the ultraviolet to 5.0 microm in the infrared is represented by a three-term Sellmeier formula to 1 x 10(-4). The temperature dependence of refractive index is similar to that of c-ZrO(2). The infrared reflectance spectrum is fitted in a classical dispersion analysis with seven oscillators derived from the transverse optical phonon as well as acoustic frequencies with splittings due to lowered symmetry derived from the randomly distributed stabilizer ions.

High-pressure reactively sputtered HfO2: Composition, morphology, and optical properties

“…These values are slightly lower than the HfO 2 bulk value ͑n = 2.08 at 600 nm͒. 29 The Figure 6 shows the XRD spectra of the HfO 2 films deposited at different pressures and the position of several reflections associated with the monoclinic phase of HfO 2 . 30 The main peak of this phase is located at 28.35°and corresponds to the 111 reflection.…”

Field-effect induced tunability in hyperbolic metamaterials

“…The refractive index of Ag has been measured by ellipsometry (See Supplemental Material Fig. S1 [57]) while the Sellmeier equation with three poles was used for the refractive index of HfO2 [58]. Under applied bias between the Ag and the ITO in the geometry of Fig.…”

Influence of Material Composition on Structural and Optical Properties of HfO2-TiO2 Mixed Oxide Coatings

“…The mechanism that might be related to the increase of n is directly related to the increase of the content of titanium in the thin films, which have significantly higher value than hafnium. Values of n for bulk HfO 2 with a monoclinic phase, and for TiO 2 with a rutile phase, are equal to 2.12 [38] and 2.65 [39], respectively. Therefore, the obtained values for thin films were slightly lower and stood out from the bulk ones.…”