Jupiter Laser Facility

Overview

JLF is an intermediate-scale, open laser facility dedicated to high-energy density science, with three operating laser systems and target areas: Titan, Janus, and COMET. JLF is the 5th highest energy laser in the US. In scale and operation, JLF is similar to lasers at the Central Laser Facility at Rutherford- Appleton Laboratory in the UK and the Laboratoire pour l’Utilisation des Lasers Intenses (LULI) located at École Polytechnique in France. Access to JLF is obtained through an annual call for proposals, and a fraction of the user time at JLF will be accessible through LaserNetUS. More than 100 Ph.D.’s have been granted that included thesis work at JLF, and the facility has been acknowledged in over 200 peer-reviewed publications. The JLF facility at LLNL provides 50% of beamtime to LaserNetUS and the other 50% is administered by LLNL through JLF annual call. These beamtime allocations are separate and duplicate proposals are discouraged. The goal of LaserNetUS is to provide complementary opportunities and not meant to replace or duplicate the annual JLF call.

Janus and Titan

After more than 10 years of operation, Janus and Titan are presently undergoing extensive refurbishment, with an expected return-to-full-operations date of March 2022. Janus and Titan refer to the target areas and to the operational mode: long-pulse (Janus) or short-pulse (Titan). They will make use of three high-energy beamlines, one of which is shared between the two target areas. All three beams employ glass amplifiers and have a 30-minute duty cycle. All experiments are hands-on for users.

Titan will have a dedicated ps beam, 0.4 to 20 ps, with energies up to 300 J at fundamental (1053 nm) into a 2-m-diam chamber; the option of full-aperture conversion to 2ω (up to 100 J) will follow later in the year. (Beam energy is limited to 120 J until new pulse-compression gratings have been qualified.) The Titan short-pulse beam uses an f/3 final optic, but f/10 can be arranged. The focal spot is < 10 μm with a strehl > 0.6. The prepulse level is better than 10^-7 (10^-14 using 2ω). Using a beam-splitter inside the chamber, the beam can be split into two differently pointed beams. A second, long-pulse, beam – 0.35-20 ns with energy up to 1 kJ (1ω) or 700 J (2ω) – can be simultaneously transported to the chamber with arbitrary timing between the beams. A mJ-level probe beam is also available.

Janus will have a dedicated long pulse beam with a second long-pulse beam available. Both beams are 0.35-20 ns with energy up to 1 kJ (1ω) or 700 J (2ω) and will have largely arbitrary pulse-shaping. Both beams have polarization control and can be detuned by ~ 1 nm in wavelength. The minimum spot size is < 20 μm with a strehl > 0.6. Phase plates are available for 200, 400, 600, 100, and 2000-μm spot sizes. A dual-echelon VISAR system and streaked optical pyrometry are standard diagnostics in Janus. A mJ-class Ti:Sapph probe is also available.

COMET

COMET is a 5-minute-rep-rate laser with either short-pulse (0.5-750 ps) or long-pulse (0.5-5 ns)  configuration and energy up to 12 J. COMET has its own cylindrical chamber. Following some brief training, users are permitted to charge and fire COMET.

More information can be found at jlf.llnl.gov.