Postdoctoral Researcher – Synchrotron Studies

The Synchrotron Studies of Materials group is looking for a post-doctoral candidate to develop coherence-enhanced dark-field x-ray microscopy (DFXM) techniques for characterizing nanometer-scale structural heterogeneity in crystalline/polycrystalline materials.

DFXM has gained recent importance at third-generation synchrotron light sources as a lens-based technique for fast micron-scale characterization of materials structure. The imminent upgrade of the Advanced Photon Source will enable a several-fold increase in coherent X-ray flux, opening up the possibility of many new types of measurements. This includes fast, targeted imaging of specific microstructural heterogeneities (defects, inclusions, interfaces) enabled by tuning the parameters of a lens-based imaging system. Through this, a variety of coupled physical phenomena in materials of interest may eventually be studied non-destructively (structural evolution, polarization, magnetization fields). This project aims to lay the foundations of such capabilities by exploiting the effects of high beam coherence in the context of DFXM experiments, in terms of theory, simulation, and experimental demonstrations. The project is primarily focused on developing new lens-based methods of rapid in situ visualization of crystallographic defects in bulk materials.

The successful candidate will be part of a highly inter-disciplinary team that conceptualizes, designs and eventually validates forward models in lens-based coherent X-ray diffraction imaging applied to microstructure characterization. This project unifies efforts in a wide range of computational and experimental areas like synchrotron experimentation, optics, wavefront analysis and solid state/materials physics. Candidates with experience in these areas are encouraged to apply.

The selected candidate will lead the effort in one or more major aspects of the project, namely: (1) design and simulation of lens-based coherent X-ray propagation/scattering models to optimally image specifically targeted types of micron-scale material heterogeneities (transmission mode, as well as analysing a Bragg-diffracted beam with a lens), (2) construction of the new DFXM system at the Sector 6 beamline of the APS, (3) validation of the developed computational methods on model structures and material systems, (4) carrying out experiments and data collection/analysis on materials of actual scientific interest. The selected candidate will present simulation, experimental and analysis results at conferences and in peer-reviewed journals.

Qualifications

• A PhD in physics, materials science, electrical engineering or equivalent (obtained within the last three years).
• Proficiency in one of the following: X-ray science, computational methods, signal/image/data processing, coherent wave optics, scientific programming, materials microstructure, synchrotron instrumentation.
• Good technical writing, communication and presentation skills.
• Willingness to learn and collaborate across different scientific disciplines in a fast-paced research environment.
• Familiarity with one or more of the following not required, but will be highly valued: 3D geometry, crystallography and reciprocal space, mathematical symmetries.

Notes

• Employer will assist with relocation costs.
• Internal number: 408933

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