NSLS-II/BNL

FIS Beamline, National Synchrotron Light Source II

Synchrotron IR is an important tool in CDAC. In the early 1990’s, the CDAC Director developed the field of high-pressure synchrotron IR microspectroscopy, which takes advantage of the high flux of synchrotron radiation at long wavelengths.  This program was begun at NSLS U2A and has transitioned to the Frontier Synchrotron Infrared Spectroscopy (FIS) beamline facility at the NSLS-II, and is managed by UIC Research Professor Zhenxian Liu and funded by NSF and DOE-NNSA through CDAC. The FIS facility has custom-built, long-working distance IR microscopes for diffraction-limited high P-T IR spectroscopy, as well as Raman spectroscopy and laser heating. With new developments/upgrades implemented, the facility allows a wide range of micro-spectroscopic studies at broad range of pressures (to over 300 GPa) and temperatures (from 5 K to several thousand K). Coupled with the synchrotron IR radiation, this facility provides diffraction-limited observation of DAC samples in cryostats or under laser heated hot spots from the far to mid-IR spectral range. We have guaranteed beam time at the FIS facility for the proposed research as a result of our management and funding of operations of the beamline.  FIS also serves as a focal point for expanding extreme conditions science to other NSLS-II beamlines, including x-ray beamlines that will be used during the downtime at the APS for its upgrade.

Available Equipment – The FIS beamline has two end stations. End Station A is a dedicated facility for experiments at simultaneous high P-T experiments utilizing the DAC and external and laser heating techniques. Major equipment at this laser-interlocked end station includes a new Vertex-80 FTIR spectrometer, a custom IR microscope with long working distance objective, a 100W CO₂ laser, an integrated optical system for temperature calibration, and a portable ruby system for pressure calibration.

End Station B is a dedicated facility for experiments at high pressure and low temperature using DACs and cryogenic techniques. The core equipment consists of a Bruker Vertex 80v FTIR spectrometer equipped with a Bruker Hyperion IR microscope, a new custom IR microscope with long working distance (40 mm) and large numerical aperture (0.5), a custom micro-Raman system, and a full range of optics and accessories capable of complete IR/visible characterization. The diamond window and vacuum optics have extended the accessible spectral range to the far IR (to 10 cm^-1).