Designing hard, low-refractive-index lossy materials for super wear-resistant absorbers

Figures & data

Figure 1. (a) XRD pattern of TiC and Ti_0.93W_0.07C films. SAED patterns of (b) TiC and (c) Ti_0.93W_0.07C films. HRTEM images of (d) TiC and (e) Ti_0.93W_0.07C films.

Figure 2. Theoretical and experimental absorption spectra, electric energy density and absorbed power density of (a, d) Al₂O₃/W/Al₂O₃/W film, (b, e) TiC/Al₂O₃/W film and (c, f) Ti_0.93W_0.07C /Al₂O₃/W film. (g) The absorption spectrum of s-polarized and p-polarized light incident at different angles in the Ti_0.93W_0.07C optical cavity.

Figure 3. The (a) refractive index and (c) extinction coefficient of W, Al₂O₃, TiC and Ti_0.93W_0.07C films. (b) A local structure diagram of Ti_0.93W_0.07C films. Green balls represent free electrons and blue balls represent localized electrons forming covalent bonds. DOS and unit cell of (d, e) Ti₁₆C₁₆ and (f, e) Ti₁₅W₁C₁₆ obtained by first-principles calculations.

Figure 4. The SEM images on the wear tracks after the ball-on-disk wear tests for (a) Al₂O₃/W, (b) TiC and (c) Ti_0.93W_0.07C optical cavities. AFM images (d–f), friction coefficients curves (g) and hardness (h) for the same optical cavities. (i) The core level spectra of XPS C1s performed on the wear tracks for Ti_0.93W_0.07C optical cavity. (j) The WCA of Al₂O₃/W, TiC and Ti_0.93W_0.07C optical cavities.

Figure 5. (a) The hardness of typical transition metal carbides, traditional dielectric materials and pure metals and their average extinction coefficient. (b) Average refractive index and extinction coefficient of typical transition metal carbides. (c) Element composition of HLLM.