High-quality Y<sub>2</sub>O<sub>3</sub>-ZrO<sub>2</sub> single-crystal rectangular waveguides have been developed for ultrahigh-temperature sensing applications. Five waveguides, 0.55–1.12 mm wide and 52–65 mm long, were fabricated from a bulky cubic 21.2-mol. % Y<sub>2</sub>O<sub>3</sub> stabilized ZrO<sub>2</sub> single crystal that had been precisely cut and finely polished. At 900-nm wavelength, the average optical loss of these waveguides is approximately 0.016 dB/cm, which is much lower than that of Y<sub>2</sub>O<sub>3</sub>-ZrO<sub>2</sub> single-crystal optical fibers grown by the laser-heated pedestal growth method. The tested waveguides survived a temperature higher than 2300 °C, and their mechanical strength and chemical resistance were also acceptable. Experimental results show that these waveguides are promising for ultrahigh-temperature sensing applications.
© 2002 Optical Society of America
(060.2290) Fiber optics and optical communications : Fiber materials
(060.2370) Fiber optics and optical communications : Fiber optics sensors
(160.4760) Materials : Optical properties
(220.5450) Optical design and fabrication : Polishing
(230.7370) Optical devices : Waveguides
Limin Tong, "Single-crystal Y2O3-ZrO2 rectangular waveguides for ultrahigh-temperature sensing applications," Appl. Opt. 41, 3804-3808 (2002)