Jesse Smith High Pressure Collaborative Access Team (HPCAT) Geophysical Laboratory, Carnegie Institution of Washington Rapid, controlled DAC (de)compression The fundamental time-resolved approach in static high pressure research 2015 IUCr High Pressure Workshop

Time – a (relatively) new DAC direction 2015 IUCr High-Pressure Workshop In static high pressure research, time is arbitrary Selected scientific challenges from HPCAT’s 2012 Workshop Explore non-equilibrium transformations and phase boundaries Elucidate dynamics, kinetics, and pathways of phase changes Study system-dependent nucleation rates and crystal growth Link to workshop report:

A few (of several) instances of P(t) 2015 IUCr High-Pressure Workshop

Overview 2015 IUCr High-Pressure Workshop Critical experimental components Source – optimized beam delivery from source to sample Pressure control – remote, programmable, precise control Detectors – short exposure, short readout, high frequency Software – high throughput processing of lots of data Examples, samples (apparatus) Fast equation of state of Mo (membrane) Ramp P↘ looking for metastable phase(s) of Ge (decompression membrane) Measuring ultrahigh (DAC) strain rates in Mo (dDAC) Synthesis of pure, amorphous Si (pneumatic rapid release box)

Source – Advanced Photon Source 2015 IUCr High-Pressure Workshop 7 GeV A high-energy 3 rd generation storage ring is crucial E(keV) ∝ E 2 (GeV) Sector 16 of the Advanced Photon Source Argonne National Laboratory Images courtesy Argonne National Laboratory

HPCAT – four dedicated HP beamlines 2015 IUCr High-Pressure Workshop ID-D Spectroscopy XES,IXS – 1eV NRIXS – 2meV ID-B Micro-diffraction Laser heating Cryostat BM-B White Laue PEC BM-D Micro-diffraction XANES Split in space keV 5-36 keV Sector 16 Bending magnet beamlines Sector 16 Canted undulator beamlines

Pressure control – traditional apparatus 2015 IUCr High-Pressure Workshop

Pressure control – contemporary control 2015 IUCr High-Pressure Workshop P t P t

Detectors – characterization in real time 100 s 2.5 s 125 Hz 3 kHz From commercial IP scanners to hybrid pixel array detectors 15 Hz

Software – must be semi-automated 2015 IUCr High-Pressure Workshop Automated peak and unit cell fitting with volume and pressure calculation Simple yet powerful software for on-line image visualization, integration, and analysis Dipotas – C. Prescher GSE_shell – P. Dera

Overview 2015 IUCr High-Pressure Workshop Critical experimental components Source – optimized beam delivery from source to sample Pressure control – remote, programmable, precise control Detectors – short exposure, short readout, high frequency Software – high throughput processing of lots of data Examples, samples, and apparatus Fast equation of state of Mo (membrane) Ramp P↘ looking for metastable phase(s) of Ge (decompression membrane) Measuring ultrahigh (DAC) strain rates in Mo (dDAC) Synthesis of pure, amorphous Si (pneumatic rapid release box)

Rapid compression (pneumatic) 2015 IUCr High-Pressure Workshop Mo + MgO Pressure apparatus—membrane Loading—500 psi/s (He) P 0 ~ 80 GPa P f ~ 210 GPa  t ~ 1.3 s Compression rate ~ 100 GPa/s Detector—DECTRIS PILATUS 1M-F Exposure period– 10 ms (100 Hz) Exposure time—7 ms Mo + MgO Pressure apparatus—membrane Loading—500 psi/s (He) P 0 ~ 80 GPa P f ~ 210 GPa  t ~ 1.3 s Compression rate ~ 100 GPa/s Detector—DECTRIS PILATUS 1M-F Exposure period– 10 ms (100 Hz) Exposure time—7 ms

2015 IUCr High-Pressure Workshop Rapid compression – equation of state High-frequency imaging yields acceptable signal- to-background ratio High-density data yields extremely robust equation of state Average compression rate ~100 GPa/s Peak compression rate ~240 GPa/s

Ramp decompression (pneumatic) 2015 IUCr High-Pressure Workshop Jodie Bradby and Bianca Haberl Development of double-sided membrane assembly for rapid, controlled sample decompression Sinogeikin et al., RSI 86, (2015)

Ramp decompression – metastable Ge phases 2015 IUCr High-Pressure Workshop Unloading (s) Haberl et al., PRB 89, (2014) Formation of R8 germanium on decompression appears to be time- independent (at least over four orders), and requires hydrostatic conditions Haberl et al., PRB 89, (2014)

2015 IUCr High-Pressure Workshop Ultrafast (step) compression (dDAC) Dynamic Compression Static Compression DAC, LVP 10 0 Strain Rate Gap Sinogeikin et al., RSI 86, (2015)

2015 IUCr High-Pressure Workshop Ultrafast (step) compression – strain rate P t Mo + MgO Pressure apparatus—dDAC Loading—1000 V (minimum rise time) P 0 ~ 151 GPa P f ~ 194 GPa  t ~ 1.25 ms Compression rate ~ 34 TPa/s Detector—DECTRIS EIGER 1M (prototype) Exposure period– 1.25 ms (800 Hz) Exposure time—1.23 ms Mo + MgO Pressure apparatus—dDAC Loading—1000 V (minimum rise time) P 0 ~ 151 GPa P f ~ 194 GPa  t ~ 1.25 ms Compression rate ~ 34 TPa/s Detector—DECTRIS EIGER 1M (prototype) Exposure period– 1.25 ms (800 Hz) Exposure time—1.23 ms Before After (  t=1.25 ms)

2015 IUCr High-Pressure Workshop Ultrafast (step) compression—strain rate Strain rate* on the order of 10 1 s -1 Even on ms time scale, signal-to- background is useable, no sign of significant peak broadening *based on a Mo

Step decompression (pneumatic quick release) 2015 IUCr High-Pressure Workshop Control Area Experimental Hutch Chuanlong Lin

Step decompression – amorphous Si synthesis 2015 IUCr High-Pressure Workshop Si Pressure apparatus—membrane + fast release Unloading— psi (maximum rate) P 0 ~ 20 GPa P f ~ 0 GPa  t ~ tens to hundreds of ms Decompression rate ~ GPa/s Detector – DECTRIS PILATUS 1M-F Exposure period–arbitrary Exposure time—arbitrary Si Pressure apparatus—membrane + fast release Unloading— psi (maximum rate) P 0 ~ 20 GPa P f ~ 0 GPa  t ~ tens to hundreds of ms Decompression rate ~ GPa/s Detector – DECTRIS PILATUS 1M-F Exposure period–arbitrary Exposure time—arbitrary

Summary 2015 IUCr High-Pressure Workshop We can leverage P(t) to: Address scientific questions in several contexts Improve experimental precision and accuracy Access intermediate strain rates Maintain static high pressure conditions after rapid  P Monitor crystal structure before, during, and after  P event Complement the mature fields of static and dynamic HP research Rapid DAC (de)compression and x-ray diffraction A new frontier in extreme conditions crystallography

Contributors and acknowledgments This work was performed at HPCAT (Sector 16), Advanced Photon Source (APS), Argonne National Laboratory. HPCAT operations are supported by DOE-NNSA under Award No. DE-NA and DOE-BES under Award No. DE-FG02-99ER45775, with partial instrumentation funding by NSF. The Advanced Photon Source is a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH P(t) development at HPCAT: Stanislav Sinogeikin, Chuanlong Lin, Eric Rod, Ligang Bai, Guoyin Shen See Smith et al., Rev. Sci. Instrum. 86, (2015) and Sinogeikin et al., Rev. Sci. Instrum. 86, (2015), User Collaboration (partial list): Jodie Bradby and Bianca Haberl; Nenad Velisavljevic, Dana Dattlebaum, and Raja Chellappa; Hyunchae Cynn and Zsolt Jenei; Choong-Shik Yoo and Dane Tomassino Software Development: Przemek Dera