Postdoctoral Researcher (M/F): Quantitative Understanding of Heat Transfer from the Surface of Iron Oxide Nanoparticles During Hyperthermia

Job Description

Missions

Scientific Background
QUANT (Quantitative Understanding of Nanoscale Heat Transport from Iron Oxide Nanoparticles' Surface during Hyperthermia) is a 42-month collaborative project funded by the French National Research Agency (ANR). It brings together five complementary partners:
- PHENIX/Sorbonne (synthesis and functionalization of magnetic iron oxide nanoparticles; project coordination),
- CEISAM/Nantes (magneto-fluorescent nanoassemblies),
- Synchrotron SOLEIL (EXAFS measurements of intraparticle temperature, WP2),
- ENS Paris (time-resolved fluorescence instrumentation for spatiotemporal thermometry, WP3),
- UPVD/PROMES (theory and modeling, WP4 — this position).

Magnetic hyperthermia is a technique in which iron oxide nanoparticles (MNPs), excited by an alternating magnetic field (AMF, 100 kHz–1 MHz), convert electromagnetic energy into heat through Néel and Brownian magnetic relaxation mechanisms. This process is quantified by the specific loss power (SLP), also known as the specific absorption rate (SAR).

While the macroscopic heating of MNP dispersions has been well characterized, the thermal landscape at the nanoscale—as well as the temperature gradient within the few nanometers surrounding an individual nanoparticle—remains largely unexplored from both experimental and theoretical perspectives.

Addressing this gap is of critical importance because understanding the effects of localized heating (such as membrane protein activation, catalysis, or drug release) requires accurate knowledge of the temperature directly at the nanoparticle surface, rather than solely in the surrounding fluid.

To date, no direct measurement of this temperature gradient around magnetic nanoparticles has been achieved. In this context, the QUANT project proposes a combined experimental and theoretical strategy to address this knowledge gap. WP4, led by UPVD/PROMES, constitutes the theoretical foundation of the ANR QUANT project.

Activity

Objectives of the Postdoctoral Research (WP4)
The postdoctoral researcher will develop and validate a theoretical framework coupling magnetic dynamics and heat transport:
— SLP/SAR Calculation
Solve the stochastic equation describing magnetization dynamics within the Langevin formalism for iron oxide nanoparticles subjected to an alternating magnetic field (AMF), taking into account size and anisotropy distributions, as well as interparticle dipolar interactions. This will make it possible to determine the dissipated power for each nanoparticle.
— Spatiotemporal Temperature Profile
Use discrete heat sources in the extended heat equation and perform analytical (e.g., using Green's function methods) and numerical calculations of the spatiotemporal temperature rise, ΔT(r,t), from the heat-generating centers into the surrounding medium.
— Observables for Direct Comparison with Experiments
SAR of the nanoparticle assembly as a function of size distribution, concentration, and dipolar interactions; ΔT(r,t) profiles to be compared with fluorescence lifetime thermometry data obtained in WP3 (ENS Paris);
Magnetization relaxation curves m(t), extracted from WP3 measurements.
— Interfacial Effects
Investigate the role of Kapitza resistance (interfacial thermal conductance) and, if necessary, the influence of an atomistic description of the internal nanoparticle structure on the temperature distribution.

Methods / Tools
- Statistical physics;
- Nanomagnetism theory;
- Stochastic Landau–Lifshitz–Gilbert (LLG) equation (Langevin formalism);
- Linear and nonlinear response theory (SAR, dynamic susceptibility);
- Analytical Green's function formalism for the heat equation in heterogeneous media;
- Numerical simulations (Python / C++);
- Atomistic spin modeling (optional).

Your Profil

Skills

Required profile
PhD in condensed-matter or theoretical physics; solid background in magnetism and/or thermal transport; demonstrable experience in numerical modelling (Python and/or C++); familiarity with stochastic differential equations or statistical physics; interest in theory-experiment interplay.

Your Work Environment

-Position details
• Duration: 18 months (ANR postdoctoral contract)
• Starting date: As early as possible in 2027 (to be agreed with the candidate)
• Location: PROMES-CNRS laboratory, Université de Perpignan Via Domitia, Perpignan, France
• Salary: Standard French ANR postdoctoral salary (∼ 2 500 euros gross/month), commensurate with experience and in accordance with current CNRS/ANR regulations
• Visa support: For non-EU/EEA candidates, the laboratory will provide the official hosting greement (convention d'accueil ) required for the visa application
• Working language: English (knowledge of French is not required, but is an asset for daily life)

The successful candidate will conduct their research at the PROMES laboratory (Perpignan/Tecnosud) under the supervision of a team of experts in the field. Regular visits and collaborative exchanges with the partner laboratories will be organized throughout the project.

Constraints and risks

No direct risks are associated with the theoretical work carried out in this project.

Compensation and benefits

Compensation

Starting from €3,040, adjustable based on experience

Annual leave and RTT

44 jours

Remote Working practice and compensation

Pratique et indemnisation du TT

Transport

Prise en charge à 75% du coût et forfait mobilité durable jusqu’à 300€

About the offer

About the CNRS

The CNRS is a major player in fundamental research on a global scale. The CNRS is the only French organization active in all scientific fields. Its unique position as a multi-specialist allows it to bring together different disciplines to address the most important challenges of the contemporary world, in connection with the actors of change.

CNRS

The research professions