Doctorat : ESR-STM on superconducting 2D materials. M/F

Job Description

Thesis Subject

In recent years, spin-dependent scanning tunneling microscopy (SP-STM) has emerged as a powerful technique for probing spin properties with atomic resolution. It can measure both spin polarization and spin-excitation spectra through inelastic tunneling spectroscopy and electron spin resonance STM (ESR-STM). A recent work[1] and measurements in the group, Fig. 1, have shown that spin-polarized and ESR-STM allowed to characterize the spin-excitation spectrum of individual Fe-phtalocyanine molecules (FePc) deposited on Ag\MgO(100).
A major objective is now to extend ESR-STM toward new systems exhibiting new types of spin excitations with non-trivial topological properties.
The first goal of the PhD is to attempt ESR-STM on magnetic phtalocyanines molecules adsorbed on superconducting NbSe2. MnPc has already shown coexisting Yu-Shiba-Rusinov states and spin-flip excitations on NbSe2[2]. After that, we will grow NbSe2 on graphene/Ir, motived by previous works showing that superconducting monolayer NbSe2 can be grown on weakly coupled graphene-based templates [3] and ESR-STM of individual spin defects in monolayer MoS2/graphene/Ir has been recently observed [4].
Further ahead, we will consider the growth of 2D magnetic halides materials, especially CrCl3, on superconducting NbSe2. The edge-localized Yu-Shiba-Rusinov states observed on this system makes it directly relevant for the study of topological spin and superconducting phenomena at the atomic scale [5].


[1] X. Zhang et al., “Electron spin resonance of single iron phthalocyanine molecules and role of their non-localized spins in magnetic interactions,” Nature Chemistry, vol. 14, pp. 59–65, Nov. 2021, doi: 10.1038/s41557-021-00827-7.
[2] S. Kezilebieke, R. Žitko, M. Dvorak, T. Ojanen, and P. Liljeroth, “Observation of Coexistence of Yu-Shiba-Rusinov States and Spin-Flip Excitations,” Nano Letters, vol. 19, pp. 4614–4619, Nov. 2018, doi: 10.1021/acs.nanolett.9b01583.
[3] K. H. Au-Yeung et al., “Atomic-Scale Quantum Control of Single Spin Defects in a Two-Dimensional Semiconductor,” Feb. 25, 2026.
[4] P. Dreher et al., “Proximity Effects on the Charge Density Wave Order and Superconductivity in Single-Layer NbSe2,” ACS Nano, vol. 15, pp. 19430–19438, Nov. 2021, doi: 10.1021/acsnano.1c06012.
[5] J. Cuperus, A. H. Kole, A. R. Botello-Méndez, Z. Zanolli, D. Vanmaekelbergh, and I. Swart, “One dimensional edge localized YSR states in CrCl3 on NbSe2,” Npj Quantum Materials, vol. 10, May 2025, doi: 10.1038/s41535-025-00759-2.

Your Work Environment

The student will participate in the experimental work of the C2N STM group (comprising four permanent staff members). This work will focus in particular on the growth of materials (graphene, NbSe2) under ultra-high vacuum conditions. These materials will subsequently be studied using STM (to analyze growth) and ESR-STM (to investigate magnetic properties).

Constraints and risks

- cryogenic fluids

Compensation and benefits

Compensation

2300 € gross monthly

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

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