Chemically stabilised ion implanted waveguides in sapphire

Formation of optical waveguides in crystals is extremely attractive for low threshold single mode lasers in materials such as ruby and titanium sapphire. Previous attempts to achieve this using helium ion implantation required unacceptable high ion doses, leading to failure of the surface. The first demonstration of waveguide formation by ion implantation to chemically stabilise defects is reported. Stable waveguides have been prepared using doses as small as 10¹⁶ ions/cm² under optimum implant conditions.