Diamond Anvil Cell Program at GSECARS

The diamond anvil cell (DAC) technique is a primary tool to study a wide range of mineral properties (melting, structure, phase relation, chemical reactions, and kinetics, transport, elastic, electronic properties, etc.) at relevant pressure-temperature conditions of planets' interior to provide new constrains on models for planetary evolution and origin. Recent breakthrough in the development of pulsed laser heating coupled with double-stage and toroid-type anvil techniques, provides capability of studying materials in situ at such ultra-extreme conditions of pressure and temperature up to 1TPa and 10,000K. These challenging experiments can only be conducted at dedicated synchrotron beamlines, like GSECARS (sector 13, APS, ANL), where the state-of-the-art techniques have been implemented and are currently being developed. These include capabilities to study in situ materials in the DAC with various degrees of crystallinity: from single crystal to powder, nano-sized and non-crystalline (amorphous solids and fluids). Combining data collection with a large area CdTe or Si 1M Pilatus detector the typical full single crystal data set takes only a few minutes, while detector synchronization with the pulsed laser and the storage ring bunch mode allows us to probe materials in the microsecond time-scale domain. To address controversial results on melting behavior, and complex phase relations of minerals across the entire pressure-temperature range of the Earth we have combined a large area CdTe 300k wide Pilatus detector with a multi-channel collimator system and double-sided laser heating. Optical and vibrational spectroscopy greatly complementing X-ray diffraction and spectroscopy techniques, becomes crucial when dealing with light elements. The advanced high-resolution user-friendly integrated optical system was recently built at GSECARS, where we have implemented Raman spectroscopy with five excitation wavelengths (266, 473, 532, 660, 946 nm), confocal imaging, double-sided IR laser heating combined with high temperature Raman (including coherent anti-Stokes Raman scattering) and transient (based on a bright supercontinuum light source) spectroscopies in a wide spectral range (200-1600 nm). Details and future developments of cutting-edge techniques at GSECARS will be discussed.