Speaker
Description
Constructing next-generation lasers with energies exceeding several megajoules, or peak powers
greater than ten petawatts, will require optical elements that tolerate significantly higher intensities than
solid-state media. For use in practical inertial confinement fusion energy plants or miniaturized particle
accelerators, these optics must also withstand harsh environments with intense backscattered light and
energetic particles. Structured gases, rather than solids, can meet these stringent requirements [1,2]. We
present the first experimental demonstration of a diffractive gas lens for steering and focusing high-energy
nanosecond to high-power femtosecond beams [3]. These lenses were constructed holographically via the
interference of two ultraviolet “write” beams (6 mJ, 5 ns, 266 nm) in an ozone-doped gas mixture. The
write beams drove a structured density profile via spatially-varied heat deposition through ultravioletinduced photodissociation of ozone [4]. The resulting lenses manipulated the focus of a third “read” beam
that was substantially more energetic (220 mJ, 5 ns, 532 nm) at an incident fluence of 35 J/cm2 with greater
than 50% efficiency. These lenses also exhibited sufficient spectral bandwidth to diffract ultrashort 35-fs
800-nm pulses. As holograms, we tuned these lenses to focus, collimate, and defocus the read beam. The
optic showed stable beam pointing and diffraction efficiency without degradation during 10 Hz operation
over sustained periods of time. These results suggest that gaseous optics may enable arbitrary, damageresistant manipulation of intense light.
This work was partially supported by NNSA Grant DE-NA0004130, NSF Grant PHY-2308641, and
the Lawrence Livermore National Laboratory LDRD program (24-ERD-001). Work performed under the
auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract
DE-AC52-07NA27344. This work was supported by the U.S. Department of Energy, Advanced Research
Projects Agency-Energy (ARPA-E), under Award Number DE-AR0002056.