Postdoctoral Position PSICHÉ Beamline

Postdoctoral Position PSICHÉ Beamline

SOLEIL Synchrotron

Saint-Aubin, France

Context and Missions:

Synchrotron SOLEIL seeks to hire a postdoc in materials science. This position is opened for the PSICHÉ beamline. The contract will last 24 months.

The PSICHÉ (Pressure Structure and Imaging by Contrast at High Energy) beamline is dedicated to X-ray diffraction under extreme conditions (pressure-temperature) and to tomography at high energy, from ambient to extreme conditions. The source is an in-vacuum wiggler that is used to produce a wide variety of beam modes, from a large parallel white/pink beam to a microfocused monochromatic beam. We have two hutches, one dedicated to white/pink beam (energy range: 15-120 keV) and another to monochromatic beam (20-50 keV). Extreme pressure and temperature conditions can be generated using different equipment: a 1200-ton multi-anvil press, Paris-Edinburgh presses (including tomography at extreme conditions), diamond anvil cells (including a double-sided laser heating facility). The use of multiple techniques, and the combination of complementary techniques, are important features of the beamline.

The scope of the scientific cases is very large: from biology and paleontology to materials science, high pressure physics and geophysics. The PSICHE beamline is a high-end facility that attracts users worldwide.

The postdoc will work on the PSICHÉ beamline under the joint supervision of Nicolas Guignot (beamline manager) and Agnès Dewaele (CEA, Commissariat à l’Energie Atomique).

She/He will be involved in the scientific, technical, and methodological aspects of the beamline team activities and will actively participate in the user support called local contact. That means preparing the beamline for the experiments, helping the users with the management of the presses, data acquisition and data treatment if necessary. This activity typically represents 3 weeks of beamtime (including week-ends) every 6 months. Working closely with renowned international researchers for limited periods of time is an important asset of the position, achieving visibility while still allowing the postdoc to conduct her.his own research program.

For this program she/he will be granted in-house research beam time and will have to submit proposals to the peer review committees.

She/He will publish her/his results and present them at national and international conferences.

Responsibility and tasks:

The postdoc research program will be divided into two tasks:

• Implementation and exploitation of acoustic emissions measurements under extreme conditions: PSICHE is equipped with a high-end large volume press experimental station designed to precisely measure various physical properties of materials, in particular liquids, at extreme conditions. Available techniques are: high-speed radiography, tomography, including high-speed (morphology, volume), xray diffraction (structure), Beer-Lambert absorption (density) and the recently added sound velocity measurements (elasticity). The beamline now seeks to implement acoustic emissions measurements, with applications in materials sciences, solid-state physics and Earth sciences. The postdoc will lead the development and integration of the technique in association with external partners and the PSICHE staff and develop a research program adapted to the new equipment. Possible topics include phase transitions studies, tracking faults and fractures in rocks or advanced materials at extreme conditions in combination with high-speed tomography, etc.;
• Exploitation of new pyrometry diagnostics + X-ray diffraction in laser heated diamond anvil cells: The PSICHÉ beamline has recently developed an innovative setup allowing for real-time measurement of sample surface temperature maps in laser heated diamond anvil cells. By combining this new technique with X-ray diffraction and thermo-mechanical modeling, and in association with external partners (CEA) and the PSICHE staff, the postdoc will be able to develop a research program adapted to her/his scientific interest, e.g. the study of crystallization kinetics, melting, thermal properties of materials under extreme conditions, etc.

In addition to these tasks, the candidate can propose other research programs.

Profile:

The candidate should have a PhD degree in physics/chemistry/materials science or Earth sciences. She/He should have a good knowledge and skills in the field of high-pressure experimentation using large volume presses and/or diamond anvil cells, in a laboratory setup or if possible in a synchrotron radiation facility, as well as a good knowledge of the condensed matter physics basics.

The postdoc will join an enthusiast and growing pluri-disciplinary team, benefiting from several national and international partnerships.

We are looking for someone showing curiosity, dynamic, autonomous, and liking working in a team.

ESSENTIAL KNOWLEDGE AND CORE SKILLS:

• Condensed matter physics. PhD (or equivalent) in physics/chemistry/materials science or Earth sciences;
• Proven expertise in high-pressure experimentation using large-volume presses and/or diamond anvil cells;
• On-call duties (local contact).

Additional and/or Complementary Knowledge and Skills

• Python programming.

Required qualities

• Curiosity;
• Dynamism;
• Autonomy;
• Ability to work in a team.

Techniques/means used

• High-pressure techniques;
• X-ray diffraction;
• X-ray imaging.