"Science Drivers for the National High Magnetic Field Laboratory’s “BigLight” Source"

Dr. John Singleton, Los Alamos National Laboratory

“BigLight” is a compact fourth-generation light source planned for the National High Magnetic Field Laboratory’s (NHMFL) quasistatic facility at Tallahassee. Designed by George Neil and his team at the Jefferson Laboratory, it is based on an RF superconducting accelerator system driving three free-electron lasers (FELs) that cover the wavelength range from 1 mm to 1.5 microns, plus a broadband THz source. BigLight’s specification was derived from a series of five workshops covering potential applications in condensed matter physics, nanoscience, biophysics, chemistry, material processing, microscopy, astrophysics and other disciplines; participants included current scientists from current FEL laboratories, potential users and international experts on light sources and high magnetic fields. Consequently, in addition to the robustness and user-friendliness demanded of a user facility, the source has several unique features, including the possibility of running the near- and mid-infrared FELs and the broadband THz source simultaneously; this will allow a wide variety of multi-color, time-resolved, pump-probe and pump-probe-probe experiments with an extremely small timing jitter between pulses. BigLight will also be able to produce either a continuous stream of micropulses (~1 ps time resolution) or flexible macropulse configurations. Co-location with the world’s highest quasistatic fields presents some unique experimental possibilities; potential users have proposed novel ultra-high-field time-resolved EPR experiments, dynamic nuclear polarization, nonlinear cyclotron resonance, interband magneto-optics, FTICR and many other techniques with very general applicability. In the talk, I will outline the scientific desiderata that have shaped the design of BigLight, and describe some of the proposed experimental techniques.