Supporting facilities for synchrotron high-pressure high/low temperature research at HPCAT, APS

High Pressure Collaborative Access Team (HPCAT) is dedicated to advancing cutting-edge, multidisciplinary, high-pressure science and technology using synchrotron radiation at Sector 16 of the Advanced Photon Source (APS) of Argonne National Laboratory. At HPCAT an array of novel x-ray diffraction and spectroscopic techniques has been integrated with high pressure and extreme temperature instrumentation. Over the last several years a number of supporting facilities have been developed and implemented to expand the available P-T range of the experimental conditions, increase efficiency and productivity of the beamlines, improve the quality of experimental data, and integrate additional methods of sample characterization with synchrotron investigations. A considerable effort was put into developing instrumentation which allows remote and automatic pressure control in diamond anvil cells (DACs) during synchrotron experiments. We have developed a number mechanical devices (gearboxes) for controlling pressure in DACs at a variety pressure and temperature conditions. Such devices can be used for automated data collection along predefined P-T paths. We also designed and implemented a double-diaphragm (membrane) pressure control system is capable of adopting many types of DAC and allows accurate sample pressure control at a variety of PT conditions - from cryogenic to laser heating experiments. These remote pressure control instrumentation can be easily integrated into cryostats and devices for high-temperature measurements at high pressure. In addition to existing cryogenic facilities, we have designed and implemented a variety of compact cryostats for different synchrotron techniques (powder and single crystal diffraction, inelastic scattering, etc.) The cryostats can accommodate a variety of standard and novel DACs, can be easily integrated with remote pressure control devices, and allow for high-pressure measurements at temperatures down to 2-4 K. We have designed a number of portable online optical systems for ruby fluorescence pressure measurements and in-situ Raman sample characterization during synchrotron experiments. Now online optical systems are available at all four experimental station at HPCAT. Combined with remote pressure control systems, they significantly increase productivity of beamlines during high-pressure experiments. We have also designed and implemented a number of offline optical system for pressure and Raman measurements, offline laser heating, IR laser micro-drilling/micromachining system for sample/gasket preparation, and so on. These and other developments will be presented and discussed during the meeting.