High-energy-density experiments at the Lawrence Livermore National Laboratory's National Ignition Facility (NIF) and the Laboratory for Laser Energetics's Omega laser require targets containing polished tantalum foils with a two-dimensional sine-wave pattern imprinted on one side (Figure 1). The peak-to-valley amplitudes and wavelengths of the sine waves are on the order of 5 μm and 50 μm -100 μm, respectively. Surface finish requirements are on the order of 20 nm R_A, and the thickness of the 3 - 5 mm diameter foils are 30 urn - 50 μm. Manufacturing these high-precision features is challenging because the tolerances are not achievable with conventional machining, and tantalum is a material that cannot be single-point diamond turned. Furthermore, physics
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