Missions

The postdoctoral researcher will be responsible for the design, synthesis, and characterization of novel flexible composite materials based on magnetic oxides, targeting electromagnetic wave absorption in the microwave frequency range (0–42 GHz). Using magnetic oxide powders provided by the industrial partner HYMAG'IN, the candidate will formulate polymer-based composites, process them into suitable geometries, and carry out a full electromagnetic characterization.

Key tasks include S-parameter measurements using a vector network analyzer (in coaxial and waveguide setups), extraction of complex permittivity and permeability spectra, and calculation of absorption performance (e.g., reflection loss RL) as a function of sample thickness and material properties, with the goal of optimizing composite formulations.

The candidate will also perform magnetic measurements (e.g., coercivity Hc, saturation magnetization Ms) to study the correlation between microstructure, composition, and functional properties. They will be expected to analyze and interpret experimental data, contribute to technical reporting, and present results during regular project meetings with partners from the HYNFINI consortium (IPCMS – THALES – HYMAG'IN).

A strong sense of autonomy is required, along with the ability to work in close collaboration with academic and industrial researchers.

Activités

Main Tasks and Responsibilities:
- Development of flexible composites based on magnetic oxides: Preparation of homogeneous mixtures of magnetic oxides (supplied by HYMAG'IN) with a polymer matrix; shaping of the composites via casting, molding, or pressing.
- Preparation and execution of electromagnetic measurements (S-parameters): Assembly of measurement setups (single-turn coaxial cell, waveguides), calibration of the vector network analyzer, and data acquisition across L, S, C, X, Ku, and Ka frequency bands.
- Extraction of complex electromagnetic properties (ε, μ) and calculation of reflection loss (RL).
- Magnetic characterization of powders and composites (e.g., coercivity Hc, saturation magnetization Ms).
- Cross-analysis of experimental results and correlation with synthesis and processing conditions.
- Preparation of technical reports and progress presentations.
- Active participation in project meetings and scientific discussions with the HYNFINI consortium partners.

Compétences

Required Skills and Expertise:
- Composite formulation (oxide/polymer mixing, molding, casting): Ability to prepare homogeneous dispersions of magnetic oxides in a polymer matrix and to fabricate composite films or plates suitable for electromagnetic measurements.
- Electromagnetic measurements (acquisition and analysis of S-parameters): Proficiency in the use of vector network analyzers (VNA), coaxial fixtures, and waveguides; solid knowledge of methods for extracting complex permittivity and permeability.
- Magnetic characterization (Hc, Ms measurements via VSM or equivalent techniques): Ability to carry out magnetic hysteresis measurements, extract key parameters such as coercivity and saturation magnetization, and interpret the results.
- Data processing and analysis: proficiency in scientific computing tools (e.g., Python) for numerical data analysis and visualization.
- Laboratory practice and safety compliance: Experience in handling laboratory equipment and strict adherence to safety protocols.

Contexte de travail

With the rapid development of electronics and telecommunications, the radiofrequency properties of materials at high frequencies are attracting growing interest—particularly in relation to their ability to absorb microwave radiation. Such materials are now critical across numerous strategic sectors, including aerospace, defense, telecommunications, and consumer electronics.
The Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS) is a joint research unit (UMR 7504) affiliated with CNRS and the University of Strasbourg. This multidisciplinary institute is organized into five departments, bringing together physicists and chemists working on advanced materials for optics, magnetism, magneto-transport, and biomedical applications.
IPCMS has recognized expertise in the development of innovative microwave-absorbing materials and has been involved in several research projects in this field. As part of the HYNFINI program, conducted in collaboration with THALES and HYMAG'IN, and funded by the French Defense Innovation Agency (AID), IPCMS contributes to the development of polymer-based composites filled with magnetic particles—particularly via tape casting—as well as to their structural, magnetic, and high-frequency characterization.
We are currently seeking a motivated postdoctoral researcher (M/F) to join the Inorganic Materials Chemistry Department, with the objective of designing and developing new absorbing materials based on magnetic oxides. Using oxides synthesized by the company HYMAG'IN (https://www.hymagin.com), the postdoc will be responsible for formulating composites, producing tape-cast films, measuring S-parameters, and extracting the complex permittivity and permeability spectra over the [0–42 GHz] frequency range. In a second phase, the postdoctoral researcher (M/F) will compute the reflection loss (RL) to evaluate and optimize the absorption efficiency of the various composites.

Le poste se situe dans un secteur relevant de la protection du potentiel scientifique et technique (PPST), et nécessite donc, conformément à la réglementation, que votre arrivée soit autorisée par l'autorité compétente du MESR.