Overview
The beamline ID15B is dedicated to the determination of structural properties of solids at high pressure using angle-dispersive-diffraction with diamond anvil cells.
The beam from an in-vacuum U20 insertion-device is focused by vertical and horizontal transfocator and monochromatized by Si(111) Bragg monochromator. The working energy for high pressure experiments is 30 keV with a flux of 1012 photons/s at 200 mA. The beam size on the sample can be varied from about 30x30 µm2 to as small as 1x1 µm2 for megabar pressure experiments.
The sample stage consists of a high-precision goniometer that is built, from the bottom to the top, by a high-precision xyz stage with a large translation range (200 mm for x and y, 100 mm for z), a rotation along z and a compact xy translation stage with a smaller translational range (50 mm) (see Figure 7). The positioning precision for the translation stages is better than 1 μm, and for the rotation, it is better than 0.001 degree. This motor stack allows precise positioning of the sample on the goniometer rotation axis and the rotation axis on the focused X-ray beam. For Friedel pair alignmement the sample can be rotate by 180 degrees.
The scattered radiation is collected Eiger 9M CdTe detector, that can be positioned in variable distances from the sample between 180 mm to 1.5 m. It can also be displaced preprendicular to the beam in both directions by 200 mm. At the minimum sample-detector distance (180 mm), a resolution down to 0.5 Å can be achieved with a full coverage at 0.7 Å.
An on-line spectrometer is available for pressure determination by the ruby fluorescence method.
It is also possible to perform Raman scattering experiments simultaneously.
The beamline is equipped with several membrane-type diamond anvil cells (0-200 GPa), a Liquid He cooled cryostat to perform high pressure experiments at low temperatures (down to 2 K), and resistive heating equipment for high temperatures up to 1500 K. An online one-sided laser-heating system has been recently installed to allow heating of the sample without removal from the sample stage.
An offline one-sided Nd-YAG laser system is available in the ID15b laboratory for high temperature annealing of samples inside the DAC. In addition a micro Raman system is available that can be used online or offline for pressure determination using the Raman signal from the diamond anvil or to measure the Raman signal from the sample.
Reference publication:
G Garbarino, ME Hanfland, S Gallego-Parra, AD Rosa, M Mezouar, D. Duran, K. Martel, E. Papillon, T. Roth, P. Got, J. Jacobs (2024) Extreme conditions x-ray diffraction and imaging beamline id15b on the esrf extremely brilliant source High Pressure Research 44 (3), 199-216