Publications de Cécile Hébert

A Multiscale Bayesian Approach to Quantification and Denoising of Energy-dispersive X-ray Data

Cécile Hébert, Duncan Thomas Lindsay Alexander

Energy dispersive x-ray (EDX) spectrum imaging yields compositional information with a spatial resolution down to the atomic level. However, experimental limitations often produce extremely sparse and noisy EDX spectra. Under such conditions, every detecte ...

IOP Publishing Ltd2025

Leveraging Machine Learning for Advanced Nanoscale X-ray Analysis: Unmixing Multicomponent Signals and Enhancing Chemical Quantification

Cécile Hébert, Duncan Thomas Lindsay Alexander

Energy dispersive X-ray (EDX) spectroscopy in the transmission electron microscope is a key tool for nanomaterials analysis, providing a direct link between spatial and chemical information. However, using it for precisely determining chemical compositions ...

American Chemical Society (ACS)2024

From STEM-EDXS data to phase separation and quantification using physics-guided NMF

Cécile Hébert, Duncan Thomas Lindsay Alexander, Guillaume Romain Obozinski, Nathanaël Perraudin

We present the development of a new algorithm which combines state-of-the-art energy-dispersive x-ray (EDX) spectroscopy theory and a suitable machine learning formulation for the hyperspectral unmixing of scanning transmission electron microscope EDX spec ...

2024

Non-negative matrix factorization-aided phase unmixing and trace element quantification of STEM-EDXS data

Cécile Hébert, Duncan Thomas Lindsay Alexander, James Badro, Farhang Nabiei

Energy-dispersive X-ray spectroscopy (EDXS) mapping with a scanning transmission electron microscope (STEM) is commonly used for chemical characterization of materials. However, STEM-EDXS quantification becomes challenging when the phases constituting the ...

Elsevier2024

espm: A Python library for the simulation of STEM-EDXS datasets

Cécile Hébert, Duncan Thomas Lindsay Alexander, Hui Chen, Guillaume Romain Obozinski, Nathanaël Perraudin

We present two open-source Python packages: "electron spectro-microscopy"(espm) and "electron microscopy tables"(emtables). The espm software enables the simulation of scanning transmission electron microscopy energy-dispersive X-ray spectroscopy datacubes ...

ELSEVIER2023

Precipitation in lean Mg-Zn-Ca alloys

Cécile Hébert, Davide Deiana

While lean Mg-Zn-Ca alloys are promising materials for temporary implants, questions remain on the impact of Zn and Ca on the microstructure. In this context, the precipitation of Zn and Ca in Mg-1.5Zn-0.25Ca (in wt.%), initially extruded at 330 & DEG;C, t ...

PERGAMON-ELSEVIER SCIENCE LTD2022

3D reconstruction of curvilinear structures with stereo matching deep convolutional neural networks

Pascal Fua, Cécile Hébert, Emad Oveisi, Gulnaz Ganeeva, Anastasiia Mishchuk, Okan Altingövde

Curvilinear structures frequently appear in microscopy imaging as the object of interest. Crystallographic defects, i.e dislocations, are one of the curvilinear structures that have been repeatedly investigated under transmission electron microscopy (TEM) ...

ELSEVIER2022

Investigating Magma Ocean Solidification on Earth Through Laser‐Heated Diamond Anvil Cell Experiments

Philippe Gillet, Cécile Hébert, Marco Cantoni, James Badro, Farhang Nabiei, Charles-Edouard Boukaré

We carried out a series of silicate fractional crystallization experiments at lower mantle pressures using the laser-heated diamond anvil cell. Phase relations and the compositional evolution of the cotectic melt and equilibrium solids along the liquid lin ...

2021

3D Ordering at the Liquid-Solid Polar Interface of Nanowires

Anna Fontcuberta i Morral, Michele Ceriotti, Cécile Hébert, Duncan Thomas Lindsay Alexander, Gözde Tütüncüoglu, Martin George Friedl, Luca Francaviglia, Mahdi Zamani, Nicolas Tappy, Giulio Imbalzano

The nature of the liquid-solid interface determines the characteristics of a variety of physical phenomena, including catalysis, electrochemistry, lubrication, and crystal growth. Most of the established models for crystal growth are based on macroscopic t ...

Wiley2020

Triplet grain growth in a-texture polycrystalline ZnO thin films

Cécile Hébert, Duncan Thomas Lindsay Alexander, Arthur Brian Aebersold

A growth of grain triplets is identified in vapor deposited, a-texture polycrystalline zinc oxide thin films, using a combination of transmission electron microscopy-based automated crystal orientation mapping and high-resolution imaging. Each triplet cons ...

2020