Fabrication of freeform potassium dihydrogen phosphate crystals by belt-on-wheel polishing for spatially tailored polarization control in high-power lasers

Urban, Nathaniel D. [Univ. of Rochester, NY (United States)] (ORCID:0000000216170114); Rinkus, Michael D. [OptiPro Systems LLC, Ontario, NY (United States)]; Gorbold, Geoffrey [OptiPro Systems LLC, Ontario, NY (United States)]; Marozas, John A. [Univ. of Rochester, NY (United States)] (ORCID:0000000204029893); Stehlik, Marek [Univ. of Rochester, NY (United States)] (ORCID:0000000302022820); Rigatti, Amy L. [Univ. of Rochester, NY (United States)] (ORCID:0009000797239905); Hoffman, Brittany N. [Univ. of Rochester, NY (United States)] (ORCID:0000000320281973); Weiner, David [Univ. of Rochester, NY (United States)]; Broege, Douglas W. [Univ. of Rochester, NY (United States)]; Marshall, Kenneth L. [Univ. of Rochester, NY (United States)]; Huff, Ray [Univ. of Rochester, NY (United States)]; Bechtold, Robert [OptiPro Systems LLC, Ontario, NY (United States)]; Bechtold, Michael J. [OptiPro Systems LLC, Ontario, NY (United States)]; Froula, Dustin H. [Univ. of Rochester, NY (United States)]; Demos, Stavros G. [Univ. of Rochester, NY (United States)] (ORCID:0000000271307398)

doi:10.1364/ao.607007

DOE OSTI · 3652971

Fabrication of freeform potassium dihydrogen phosphate crystals by belt-on-wheel polishing for spatially tailored polarization control in high-power lasers

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Abstract

Large-aperture (>30 cm) optical components that provide spatially tailored control of the properties of a laser beam, such as phase, polarization, and amplitude, have been the focus of much research and development in recent years. Such optics can improve energy throughput and target implosion efficiency in high-power laser systems conducting inertial confinement fusion research. Here, a method is demonstrated for fabricating freeform surface topographies into the birefringent crystalline material, potassium dihydrogen phosphate (KDP). Belt-on-wheel polishing with an oil-based fluid, developed to mitigate the deliquescent properties of KDP, is used to deterministically polish a freeform topography into KDP, enabling the fabrication of a wave plate with spatially arbitrary retardance. Testing of the laser-induced damage threshold of belt-on-wheel polished KDP was conducted at a wavelength of 351 nm and a pulse duration of 1 ns. The results revealed that the polished surfaces are highly resistant to laser-induced damage, making them suitable for large-aperture, high-power laser applications.

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Urban, Nathaniel D. [Univ. of Rochester, NY (United States)] (ORCID:0000000216170114), Rinkus, Michael D. [OptiPro Systems LLC, Ontario, NY (United States)], Gorbold, Geoffrey [OptiPro Systems LLC, Ontario, NY (United States)], Marozas, John A. [Univ. of Rochester, NY (United States)] (ORCID:0000000204029893), Stehlik, Marek [Univ. of Rochester, NY (United States)] (ORCID:0000000302022820), Rigatti, Amy L. [Univ. of Rochester, NY (United States)] (ORCID:0009000797239905), Hoffman, Brittany N. [Univ. of Rochester, NY (United States)] (ORCID:0000000320281973), Weiner, David [Univ. of Rochester, NY (United States)], Broege, Douglas W. [Univ. of Rochester, NY (United States)], Marshall, Kenneth L. [Univ. of Rochester, NY (United States)], Huff, Ray [Univ. of Rochester, NY (United States)], Bechtold, Robert [OptiPro Systems LLC, Ontario, NY (United States)], Bechtold, Michael J. [OptiPro Systems LLC, Ontario, NY (United States)], Froula, Dustin H. [Univ. of Rochester, NY (United States)], Demos, Stavros G. [Univ. of Rochester, NY (United States)] (ORCID:0000000271307398). 2026-08-20. Fabrication of freeform potassium dihydrogen phosphate crystals by belt-on-wheel polishing for spatially tailored polarization control in high-power lasers. https://doi.org/10.1364/ao.607007

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