LUAB nonlinear optical crystal looks good for use in the UV

Aug. 7, 2013
Another candidate nonlinear optical crystal is entering the field: lutetium aluminum borate, or LuAl3(BO3)4 (abbreviated as LuAB).

Another candidate nonlinear optical crystal is entering the field: lutetium aluminum borate, or LuAl3(BO3)4 (abbreviated as LuAB). Engineers at the Chinese Academy of Sciences (Fuzhou, China) have characterized the optical properties of LuAB, finding that the UV cutoff wavelength of the crystal is 178 nm and its birefringence -(no - ne) is in the range of 0.067 to 0.088 between the near IR and the UV spectral regions, with example indices no and ne of 1.8563 and 1.7681, respectively, at a 266 nm wavelength.

The researchers grew the crystals themselves, using a top-seeded solution-growth (TSSG) method to produce colorless, transparent crystals weighing more than 40 g and on the order of 20 mm in size. The material is phase-matchable in the regions from 0.49 to 1.4 μm for type-I and 0.65 to 1.4 μm for type-II frequency-doubling, respectively. Under test; the material showed an effective nonlinear coefficient as high as 1.03 pm/V for type I frequency-doubling at longer wavelengths. The walkoff angle for type-I phase-matching varies between about 5 and 45 mrad for fundamental wavelengths between 0.49 and 0.68 μm. The crystal has a smaller walk-off angle and larger acceptance angle than beta-barium borate (BBO), an often-used conventional nonlinear optical material. In addition, LuAB has a wider range of phase-matching angles in the UV region and is resistant to thermal shock, moisture, and acids. The researchers are now trying to grow larger LuAB crystals. Contact Ning Ye at [email protected].

About the Author

John Wallace | Senior Technical Editor (1998-2022)

John Wallace was with Laser Focus World for nearly 25 years, retiring in late June 2022. He obtained a bachelor's degree in mechanical engineering and physics at Rutgers University and a master's in optical engineering at the University of Rochester. Before becoming an editor, John worked as an engineer at RCA, Exxon, Eastman Kodak, and GCA Corporation.

Sponsored Recommendations

March 31, 2025
Enhance your remote sensing capabilities with Chroma's precision-engineered optical filters, designed for applications such as environmental monitoring, geospatial mapping, and...
March 31, 2025
Designed for compatibility with a wide range of systems, Chroma's UV filters are engineered to feature high transmission, superior out-of-band blocking, steep edge transitions...
March 31, 2025
Discover strategies to balance component performance and system design, reducing development time and costs while maximizing efficiency.
March 31, 2025
Filter accessories including cubes, sliders, and rings, designed to enhance the performance and versatility of optical systems. These components ensure precise alignment and stability...

Voice your opinion!

To join the conversation, and become an exclusive member of Laser Focus World, create an account today!