Postdoc (M/F) 4D synchrotron X-ray diffraction imaging of grain growth

CNRS; France; On-site; EUR 42,000 - 56,000; Full time

Job summary

CNRS at ESRF invites applicants for a First Stage Researcher position in Materials Engineering. You will develop a unified reconstruction framework to extract lattice orientation and elastic strain from high-end X-ray imaging data, extending existing codes to new beam configurations.

The role demands experience in image processing, tomographic reconstruction, and inverse problems, with strong Python and MATLAB skills, and the ability to work across institutes in an international setting.

Qualifications

• PhD in physics, computational imaging, applied mathematics, or a related field.
• Experience in image processing, tomographic reconstruction, and inverse problems.
• Knowledge of crystallography and X-ray or electron diffraction.
• Programming skills in Python and MATLAB.
• Ability to work within a multidisciplinary team across multiple institutes and fluent in English.

Responsibilities

• Develop a unified reconstruction framework for 3D lattice orientation and elastic strain imaging from MTt data.
• Implement a forward model based on kinematic diffraction for monochromatic and pink-beam configurations.
• Design and validate a 6D reconstruction scheme (2D orientation, 1D strain) across modalities.
• Validate reconstructions against near-field DCT/TT, 3DXRD, and DFXM data.
• Release code with documentation and unit tests; publish results and present at conferences.

Skills

Computational imaging

Image processing

Inverse problems

Multidisciplinary teamwork

Education

PhD in physics or related field

Tools

Python

MATLAB

Job description

Organisation/Company CNRS Department Matériaux Ingénierie et Science Research Field Engineering Physics Acoustics Engineering Materials engineering Researcher Profile First Stage Researcher (R1) Application Deadline 5 Nov 2026 - 23:59 (UTC) Country France Type of Contract Temporary Job Status Full-time Hours Per Week 35 Offer Starting Date 1 Jan 2027 Is the job funded through the EU Research Framework Programme? Not funded by a EU programme Is the Job related to staff position within a Research Infrastructure? No

Offer Description

You will develop a unified reconstruction framework that goes beyond 3D reconstruction of grain morphology, enabling the extraction of local lattice orientation and elastic strain from magnified topotomography (MTT) acquisitions performed on the Hard X-ray Diffraction Microscopy (ID03) beamline at the ESRF. Building on the existing DCT code base developed for near-field acquisitions without X-ray optical magnification, you will extend its applicability to X-ray dark-field microscopy using refractive lenses. You will first establish and validate the method in a monochromatic beam configuration, before extending it to the pink-beam case to achieve higher flux and faster acquisitions.

• Implement and validate a forward model based on kinematic diffraction to simulate monochromatic MTT projection images, and subsequently extend it to the pink beam case;
• Implement an iterative 6D reconstruction scheme that recovers spatially resolved (3D) maps of lattice orientation (2D) and elastic strain (1D), first from monochromatic MTT acquisitions and then from pink-beam MTT acquisitions;
• Validate both reconstructions against complementary techniques acquired in monochromatic beam conditions, namely near-field DCT/TT, scanning 3DXRD (s 3DXRD), and DFXM;
• Release the corresponding code with comprehensive documentation and unit tests;
• Publish the simulation and experimental results and present them at international conferences.

You will be a key player in the collaborative research project 4DGG, which investigates grain growth in polycrystalline metals using 4D (3D + time) synchrotron diffraction imaging. Funded by the French National Research Agency (ANR), the project is coordinated and hosted at ESRF (Can Yıldırım) in partnership with the MATEIS laboratory at INSA Lyon (Wolfgang Ludwig) and CEMEF at Mines Paris (Marc Bernacki).

You are enthusiastic about computational imaging and have experience in solving inverse problems. You enjoy scientific programming and thrive in collaborative, international environments, while also being able to work independently.

To be considered for this position, you should meet the following requirements:

• A PhD in physics, computational imaging, applied mathematics, or a related field;
• Experience in image processing, tomographic reconstruction, and associated inverse problems;
• Knowledge of crystallography and X-ray or electron diffraction;
• Programming skills in Python and MATLAB;
• The ability to work effectively within a multidisciplinary team across multiple institutes;
• Good command of English (the working language at the ESRF).