Optical transmission, dispersion, and transition behavior of ZnGa₂O₄transparent ceramic

Abstract

As an emerging transparent ceramic with extremely wide transmission range, the unique optical properties of ZnGa2O4 are of particular interest. In this work, ZnGa2O4 transparent ceramic with high optical quality was prepared by pressureless sintering and hot isostatic pressing. Its optical behavior was then comprehensively studied. The critical optical data, including refractive index, extinction coefficient, Abbé number, absorption coefficient in infrared region, and phonon frequency, were investigated. The indirect band gap and the phonon energy assisting indirect transition were determined as 4.10 and 0.17 eV, respectively. The modified Sellmeier equation and single‐oscillator dispersion relation were derived to describe the optical dispersion. Benefitting from the weaker tetrahedral Zn–O bond and heavier cationic masses, the infrared transmission range of ZnGa2O4 transparent ceramic was broadened significantly. Oxygen vacancies were suggested to induce the absorption in lower photon energy region of ZnGa2O4 transparent ceramic, which may enrich its functionalization. This work is meaningful for gaining overall insight into optical properties of transparent materials.

Influence of vacancies on the optical and electronic properties of the rhombohedral In2O3 oxide

“…To study the influence of vacancy on the optical and electronic properties, the optical properties of the rhombohedral In 2 O 3 with In‐vacancy (V ‐In ) and O‐vacancy (V ‐O ) are analyzed. Here, we study two important optical parameters: energy loss functional and adsorption coefficient 58–62 . The optical properties of the rhombohedral In 2 O 3 with In‐vacancy (V ‐In ) and O‐vacancy (V ‐O ) are calculated with electronic transition, which is given by 63 : $$$$\begin{equation}\varepsilon (\omega ) = {\varepsilon }_1(\omega ) + i{\varepsilon }_2(\omega ).\end{equation}$$$$…”

“…Here, we study two important optical parameters: energy loss functional and adsorption coefficient. [58][59][60][61][62] The optical properties of the rhombohedral In 2 O 3 with In-vacancy (V -In ) and O-vacancy (V -O ) are calculated with electronic transition, which is given by 63 :…”

Refractive index dispersion prediction for garnets (A3B2C3X12)

“…Since V m is independent of wavelength, all wavelength dependence must be captured in α T . Since n 2 ‐1 is known to have Sellmeier functionality, α T must also have the same wavelength dependence 36,38,41–46 . The approximation is equivalent to the assumption that ( c ‐ 4π/3) is 0, rather than −2, to preserve the Sellmeier functionality and vastly simplify the numerical analysis.…”

“…Since n 2 -1 is known to have Sellmeier functionality, α T must also have the same wavelength dependence. 36,38,[41][42][43][44][45][46] The approximation is equivalent to the assumption that (c -4π/3) is 0, rather than −2, to preserve the Sellmeier functionality and vastly simplify the numerical analysis. The wavelength dependence of the polarizabilities, α ei [λ] and α • an [λ], were defined using a two-term function, similar to a Sellmeier function:…”

Sintering of Lixiviated Nano Glass-Ceramics: An Original Route to Elaborate Transparent Ceramics

“…Transparent ceramics have raised significant attention during the last decades due to their promising and remarkable combination of optical, mechanical, dielectric and thermal properties [1][2][3][4][5][6][7]. Transparent crystalline materials can be obtained through different synthesis routes using i) the Czochralski, Verneuil or flux growing methods for example to get high quality single crystals [8][9][10], ii) the sintering of nano-powders by vacuum sintering [11], hot uniaxial or isostatic pressing (HP/HIP) [12,13] and iii) non-conventional sintering techniques like the Spark Plasma Sintering (SPS) [14,15].…”