High-pressure and high-temperature neutron-diffraction experiments using Kawai-type multi-anvil assemblies

Sano, Asami   ; Kakizawa, Sho*; Shito, Chikara*; Hattori, Takanori   ; Machida, Shinichi*; Abe, Jun*; Funakoshi, Kenichi*; Kagi, Hiroyuki*

We applied Kawai-type multi-anvil assemblies (MA6-8) for time-of-flight neutron-diffraction experiments to achieve high pressures and high temperatures simultaneously. To achieve sufficient signal intensities, the angular access to the sample was enlarged using slits and tapers on the first-stage anvils. Using SiC-binder sintered diamond for the second-stage anvils that transmits neutrons, sufficient signal intensities were achieved at a high-pressure of 23.1 GPa. A high-temperature experiment was also conducted at 16.2 GPa and 973 K, validating the use of tungsten carbide for the second-stage anvils. The present study reveals the capability of the MA6-8 cells in neutron-diffraction experiments to attain pressures and temperatures beyond the limits of the conventional MA6-6 cells used in the high-pressure neutron diffractometer PLANET at the MLF, J-PARC.