Nonlinear optical crystals and their manufacture and use
View Patent ↗Described are nonlinear optical (NLO) crystals, including aluminum-borate NLO crystals, that have low concentrations of contaminants that adversely affect the NLO crystal's optical properties, such as compounds that contain transition-metal elements and/or lanthanides, other than yttrium, lanthanum, and lutetium. Some NLO crystals with low concentrations of these contaminants are capable of second harmonic generation at very short wavelengths. Also described are embodiments of a method for making these NLO crystals. Some embodiments involve growing a single NLO crystal, such as an aluminum-borate NLO crystal, from a mixture containing a solvent that is substantially free of harmful contaminants. The described NLO crystals can be used, for example, in laser devices.
1. A nonlinear optical crystal for use with a laser to generate a laser beam, the nonlinear optical crystal having a formula (Y 1-x Lu x )Al 3 (BO 3 ) 4 where X=0-1, a volume greater than about 0.1 mm 3 and comprising less than about 100 ppm by weight of any element that inhibits the ability of the nonlinear optical crystal to generate and/or emit light at wavelengths less than about 300 nm.
2. The nonlinear optical crystal of claim 1 , where the nonlinear optical crystal has a formula LuAl 3 (BO 3 ) 4 .
3. A nonlinear optical crystal for use with a laser to generate a laser beam, the nonlinear optical crystal having a formula YAl 3 (BO 3 ) 4 , a volume greater than about 0.1 mm 3 and comprising less than about 100 ppm by weight of any element that inhibits the ability of the nonlinear optical crystal to generate and/or emit light at wavelengths less than about 300 nm.
4. A YAl 3 (BO 3 ) 4 nonlinear optical crystal for use with a laser to generate a laser beam, the YAl 3 (BO 3 ) 4 nonlinear optical crystal having a volume greater than about 1 mm 3 and being capable of converting an input laser beam of a first wavelength into an output laser beam of a second wavelength, where the second wavelength is less than about 200 nm.
5. The nonlinear optical crystal of claim 1 wherein the crystal is YAl 3 (BO 3 ) 4 doped with La or W.
6. A method of generating a laser beam, comprising:
selecting a nonlinear optical crystal having a formula (Y 1-x Lu x )Al 3 (BO 3 ) 4 where X=0-1, a volume greater than about 0.1 mm 3 and comprising less than about 100 ppm by weight of any element that inhibits the ability of the nonlinear optical crystal to generate and/or emit light at wavelengths less than about 300 nm; and
directing an input laser beam at the nonlinear optical crystal to generate and/or emit an output laser beam exiting the nonlinear optical crystal, where the output laser beam has a wavelength less than about 300 nm.
7. The method of claim 6 , where the nonlinear optical crystal is a YAl 3 (BO 3 ) 4 crystal doped with La or W.
8. The method of claim 6 , where the nonlinear optical crystal is a YAl 3 (BO 3 ) 4 crystal or a LuAl 3 (BO 3 ) 4 crystal.
9. A method, comprising:
directing an input laser beam at a nonlinear optical crystal to generate and/or emit an output laser beam having a wavelength less than about 300 nm, the nonlinear optical crystal having a formula (Y 1-x Lu x )Al 3 (BO 3 ) 4 where X=0-1, a volume greater than about 0.1 mm 3 and comprising less than about 100 ppm by weight of any element that inhibits the ability of the nonlinear optical crystal to generate and/or emit light at wavelengths less than about 300 nm; and
directing the output laser beam at a substrate to detect anomalies on the surface of the substrate.
10. A method, comprising:
directing an input laser beam at a nonlinear optical crystal to generate and/or emit an output laser beam having a wavelength less than about 300 nm, the nonlinear optical crystal having a formula (Y 1-x Lu x Al 3 (BO 3 ) 4 where X=0−1, volume greater than about 0.1 mm 3 and comprising less than about 100 ppm by weight of any element that inhibits the ability of the nonlinear optical crystal to generate and/or emit light at wavelengths less than about 300 nm; and
directing the output laser beam at a substrate to bore a hole in the substrate.
11. The YAl 3 (BO 3 ) 4 nonlinear optical crystal according to claim 4 where the second wavelength is less than about 175 nm.