Before the deposition on the Er:Al2O3 Lively material, the coupling circuit, i.e., the strip waveguides, the mode transition tapers as well as mode converters had been lined having a 800?nm thick layer of hydrogen silsesquioxane (HSQ, n?~1.forty five) to stop their coating Together with the Lively product, as shown in Fig. 1. The HSQ cladding was