@article{Haberl2022,

title = {Multi-Extreme Conditions at the Second Target Station},

author = {B. Haberl and D. G. Quirinale and C. Li and G. E. Granroth and H. Nojiri and M.-E. Donnelly and S. V. Ushakov and R. Boehler and B. L. Winn},

url = {https://aip.scitation.org/doi/10.1063/5.0093065},

doi = {10.1063/5.0093065},

year  = {2022},

date = {2022-08-22},

journal = { Review of Scientific Instruments},

volume = {93},

number = {083907},

issue = {8},

abstract = {Three concepts for the application of multi-extreme conditions under in situ neutron scattering are described here. The first concept is a neutron diamond anvil cell made from a non-magnetic alloy. It is shrunk in size to fit existing magnets and future magnet designs and is designed for best pressure stability upon cooling. This will allow for maximum pressures above 10 GPa to be applied simultaneously with (steady-state) high magnetic field and (ultra-)low temperature. Additionally, an implementation of miniature coils for neutron diamond cells is presented for pulsed-field applications. The second concept presents a set-up for laser-heating a neutron diamond cell using a defocused CO2 laser. Cell, anvil, and gasket stability will be achieved through stroboscopic measurements and maximum temperatures of 1500 K are anticipated at pressures to the megabar. The third concept presents a hybrid levitator to enable measurements of solids and liquids at temperatures in excess of 4000 K. This will be accomplished by a combination of bulk induction and surface laser heating and hyperbaric conditions to reduce evaporation rates. The potential for deployment of these multi-extreme environments within this first instrument suite of the Second Target Station is described with a special focus on VERDI, PIONEER, CENTAUR, and CHESS. Furthermore, considerations for deployment on future instruments, such as the one proposed as TITAN, are discussed. Overall, the development of these multi-extremes at the Second Target Station, but also beyond, will be highly advantageous for future experimentation and will give access to parameter space previously not possible for neutron scattering.},

keywords = {extreme environment, high pressure, instrument, neutron scattering},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Thermal Conductivity of BAs under Pressure},

author = {Songrui Hou and Bo Sun and Fei Tian and Qingan Cai and Youming Xu and Shanmin Wang and Xi Chen and Zhifeng Ren and Chen Li and Richard B. Wilson},

url = {https://onlinelibrary.wiley.com/doi/10.1002/aelm.202200017},

doi = {10.1002/aelm.202200017},

year  = {2022},

date = {2022-07-22},

urldate = {2022-07-22},

journal = {Advanced Electronic Materials},

number = {2200017},

abstract = {The thermal conductivity of boron arsenide (BAs) is believed to be influenced by phonon scattering selection rules due to its special phonon dispersion. Compression of BAs leads to significant changes in phonon dispersion, which allows for a test of first principles theories for how phonon dispersion affects three- and four-phonon scattering rates. This study reports the thermal conductivity of BAs from 0 to 30 GPa. Thermal conductivity vs. pressure of BAs is measured by time-domain thermoreflectance with a diamond anvil cell. In stark contrast to what is typical for nonmetallic crystals, BAs is observed to have a pressure independent thermal conductivity below 30 GPa. The thermal conductivity of nonmetallic crystals typically increases upon compression. The unusual pressure independence of BAs's thermal conductivity shows the important relationship between phonon dispersion properties and three- and four-phonon scattering rates.},

keywords = {high pressure, phonon, thermal transport},

pubstate = {published},

tppubtype = {article}

}

@article{Cai2021,

title = {Pressure- and temperature-dependent inelastic neutron scattering study of the phase transition and phonon lattice dynamics in para-terphenyl},

author = {Qingan Cai and Michael McIntire and Luke L. Daemen and Chen Li and Eric L. Chronister},

url = {https://pubs.rsc.org/en/content/articlelanding/2021/cp/d1cp00190f#!divAbstract},

doi = {10.1039/D1CP00190F},

year  = {2021},

date = {2021-03-24},

journal = {Physical Chemistry Chemical Physics},

volume = {23},

pages = {8792},

abstract = {Inelastic neutron scattering has been performed on para-terphenyl at temperatures from 10 to 200 K and under pressures from the ambient pressure to 1.51 kbar. The temperature dependence of phonons, especially low-frequency librational bands, indicates strong anharmonic phonon dynamics. The pressure- and temperature-dependence of the phonon modes suggest a lack of phase transition in the region of 0\textendash1.51 kbar and 10\textendash30 K. Additionally, the overall lattice dynamics remains similar up to 200 K under the ambient pressure. The results suggest that the boundary between the ordered triclinic phase and the third solid phase, reported at lower temperatures and higher pressures, is out of the pressure and temperature range of this study.},

keywords = {high pressure, phonon, Raman},

pubstate = {published},

tppubtype = {article}

}

@article{Haberl2017b,

title = {Wide-angle diamond cell for neutron scattering},

author = {Bianca Haberl and Sachith Dissanayake and Feng Ye and Luke L. Daemen and Yongqiang Cheng and Chen W. Li and A.-J. Ramirez-Cuesta and Masaaki Matsuda and Jamie J. Molaison and Reinhard Boehler},

url = {https://www.tandfonline.com/doi/full/10.1080/08957959.2017.1390571},

doi = {10.1080/08957959.2017.1390571},

year  = {2017},

date = {2017-10-19},

journal = {High Pressure Research},

volume = {37},

number = {4},

pages = {495-506},

abstract = {A new diamond cell with extreme apertures is described. It is tailored for a large variety of neutron scattering techniques such as inelastic neutron scattering and single-crystal diffraction both at the Spallation Neutron Source (SNS) and the High Flux Isotope Reactor at the Oak Ridge National Laboratory. Simple springs enable forces of over 10 metric tons to be clamped in for low-temperature measurements. At present, low-cost polycrystalline diamond (Versimax) pressure anvils are used. We predict a routine pressure regime up to 20 GPa with sample volumes of ∼0.5 mm3. Future use of large CVD single-crystal diamond anvils will significantly expand this pressure range. We show examples for measurements at the SNAP, VISION and CORELLI beamlines of the SNS.},

keywords = {diamond anvil cell, diffraction, high pressure, neutron scattering},

pubstate = {published},

tppubtype = {article}

}