METHOD AND APPARATUS FOR PULSED HARMONIC ULTRAVIOLET LASERS
An apparatus for producing coherent, pulsed ultraviolet light with pulse durations that range between 1 ps and 1 μs includes one or more source lasers in the visible or near-infrared frequency range. The apparatus also includes one or more FC stages, at least one of the one or more FC stages including a nonlinear FC device and one or more optical elements. The optical elements include a reflector, a focusing element, a polarization-controlling optic, a wavelength separator, or a fiber optic component. The FC device includes a huntite-type aluminum double borate nonlinear optical material configured to produce FC light having a wavelength between 190 and 350 nm and a composition given by RAl 3 B 4 O 12 , where R comprises one or a plurality of elements {Sc, La, Y, Lu}. The nonlinear optical material is characterized by an optical transmission greater than 70% over the wavelength range of 190 to 350 nm.
1 . An apparatus for producing coherent, pulsed, ultraviolet light, the apparatus comprising:
one or more source lasers configured to provide visible or near-infrared output radiation; and
one or more frequency conversion stages, at least one of the one or more frequency conversion stages including a nonlinear frequency conversion device and one or more optical elements including: a reflector, a focusing element, a polarization-controlling optic, a wavelength separator, or a fiber optic component; and
wherein the nonlinear frequency conversion device includes a nonlinear optical material producing frequency converted light having a wavelength between 190 and 350 nm and experiences a local peak intensity greater than 5 GW/cm 2 during operation.
2 . The apparatus of claim 1 wherein the frequency converted light is output light of the apparatus.
3 . The apparatus of claim 1 wherein the local peak optical intensity ranges from about 5-10 GW/cm 2 .
4 . The apparatus of claim 1 wherein the local peak optical intensity ranges from about 10-20 GW/cm 2 .
5 . The apparatus of claim 1 wherein the local peak optical intensity ranges from about 20-30 GW/cm 2 .
6 . The apparatus of claim 1 wherein the local peak optical intensity ranges from about 30-50 GW/cm 2 .
7 . The apparatus of claim 1 wherein the local peak optical intensity is greater than 50 GW/cm 2 .
8 . The apparatus of claim 1 wherein the nonlinear frequency conversion device comprises a huntite-type aluminum double borate material having a composition given by RAl 3 B 4 O 12 , where R is one or a plurality of elements {Sc, La, Y, Lu}.
9 . The apparatus of claim 8 wherein the composition is given by
Y (1-x) La x Al 3 B 4 O 12 , with 0≦x≦0.4.
10 . The apparatus of claim 9 wherein x is about 0.25.
11 . The apparatus of claim 9 wherein x=0.
12 . The apparatus of claim 8 wherein the composition is given by
Lu (1-x) La x Al 3 B 4 O 12 , with 0≦x≦0.4.
13 . The apparatus of claim 1 wherein the one or more source lasers comprises a single source laser having a nominal angular frequency w and wherein an output of the apparatus includes one or more of nominal angular frequencies: 2ω, 3ω, 4ω, 5ω, 6ω, 7ω, or 8ω.
14 . An apparatus for producing coherent, pulsed, ultraviolet light, the apparatus comprising:
one or more source lasers with visible or near-infrared output radiation; and
one or more frequency conversion stages, at least one of the one or more frequency conversion stages including a nonlinear frequency conversion device and one or more optical elements including: a reflector, a focusing element, a polarization-controlling optic, a wavelength separator, or a fiber optic component; and;
wherein the nonlinear frequency conversion device includes a nonlinear optical material configured to produce frequency converted light having a wavelength between 190 and 350 nm, and wherein the nonlinear optical material operates with a time-averaged local optical intensity greater than about 50 MW/cm 2 .
15 . The apparatus of claim 14 wherein the time-averaged local optical intensity ranges from about 50-100 MW/cm 2 .
16 . The apparatus of claim 14 wherein the time-averaged local optical intensity ranges from about 100-250 MW/cm 2 .
17 . The apparatus of claim 14 wherein the time-averaged local optical intensity ranges from about 250-500 MW/cm 2 .
18 . The apparatus of claim 14 wherein the time-averaged local optical intensity is greater than about 500 MW/cm 2 .
19 . The apparatus of claim 14 wherein the frequency converted light is output light of the apparatus.
20 . An apparatus for producing coherent, pulsed, ultraviolet light, the apparatus comprising:
one or more source lasers emitting radiation in the visible or near-infrared frequency range;
one or more frequency conversion stages, at least one of the one or more frequency conversion stages including a nonlinear frequency conversion device configured to receive light propagating along an optical path passing through the nonlinear frequency conversion device and one or more optical elements including: a reflector, a focusing element, a polarization-controlling optic, a wavelength separator, or a fiber optic component, wherein the nonlinear frequency conversion device includes:
a thermally-conducting mount having a first side, a second side opposing the first side and a passage extending from the first side to the second side, wherein the passage defines a mounting surface;
a nonlinear optical device having opposing facets having a component perpendicular to the propagation axis and an exterior surface extending between the opposing facets at a periphery of the nonlinear optical crystal, the nonlinear optical crystal being mounted in the thermally-conducting mount; and
a solder containing a metal material disposed between the mounting surface of the thermally-conducting mount and the exterior surface of the nonlinear optical crystal.
21 . The apparatus of claim 20 wherein the nonlinear optical crystal produces frequency converted light having a wavelength between 190 and 350 nm, and wherein the nonlinear optical crystal experiences an average optical intensity greater than 50 MW/cm 2 during operation.
22 . The apparatus of claim 20 wherein the solder makes contact with an entirety of the mounting surface of the thermally-conducting mount and an entirety of the exterior surface of the nonlinear optical crystal.
23 . The apparatus of claim 20 further comprising a water or solvent soluble wetting or fluxing agent, wherein the solder is characterized by a melting point below 900 K.
24 . The apparatus of claim 20 wherein the nonlinear optical crystal comprises a huntite-type aluminum double borate material having a composition given by RAl 3 B 4 O 12 , where R is one or a plurality of elements {Sc, La, Y, Lu}.
25 . The apparatus of claim 24 wherein the composition is given by
Y (1-x) La x Al 3 B 4 O 12 , with 0≦x≦0.4.
26 . The apparatus of claim 25 wherein x is about 0.25.
27 . The apparatus of claim 25 wherein x=0.
28 . The apparatus of claim 24 wherein the composition is given by
Lu (1-x) La x Al 3 B 4 O 12 , with 0≦x≦0.4.