We have a “new” (used) Nd:YAG pulsed laser (labelled Nd:YAG B in the photo below) that can produce up to 600 mJ of 1064 nm light in 6 ns pulses which we frequency double to 532 nm to pump our Radiant Dyes Narrowscan laser. The dye laser has a high-power, narrow bandwidth (5 GHz), near infra-red (730-750 nm) output.
As before, the 1064nm output of the “old” Nd:YAG (labelled as Nd:YAG A) is doubled to 532 nm and the sum-frequency of the first and second harmonic is used to generate 170 mJ of 355 nm light. This third harmonic pumps the Sirah Cobra-Stretch laser (another dye laser), which outputs broadband (85 GHz) 486 nm pulses that are then doubled to 243 nm (UV).
The laser systems (A and B) are completely independent, so we can easily fine-tune the timing of the two and optimise the two-step excitation process.
 Selective Production of Rydberg-Stark States of Positronium. T. E. Wall, A. M. Alonso, B. S. Cooper, A. Deller, S. D. Hogan, and D. B. Cassidy, Phys. Rev. Lett. 114, 173001 (2015) DOI:10.1103/PhysRevLett.114.173001.