Ahead of the deposition in the Er:Al2O3 Energetic product, the coupling circuit, i.e., the strip waveguides, the mode transition tapers plus the manner converters were coated that has a 800?nm thick layer of hydrogen silsesquioxane (HSQ, n?~one.45) to stop their coating Along with the Lively material, as demonstrated in Fig. one. The HSQ cladding