Home » Physics of low dimensionality systems

Physics of low dimensionality systems

Scientific objectives

  • Synthesize new 2D materials and 2D-based hybrid heterostructures
  • Control and modify their electronic properties by functionalizing these 2D materials.
  • Study and control supramolecular self-assembly process to synthesize perfect 2D or 3D monocrystals and study their physical properties to functionalize other materials and find applications for example in organic solar cells.
  • To investigate the growth and the magneto-electronic properties of ferromagnetic metal/organic semiconductor hybrid heterostructures.


Dominique AUBEL
Assistant professor


Assistant professor

Research scientist

Assistant professor

Emmanuel DENYS
Assistant engineer

Assistant professor

Assistant engineer

Guillaume GARREAU
Assistant professor


Assistant professor

Carmelo PIRRI

Laurent SIMON
Principal Investigator

François VONAU
Assistant professor

Patrick WETZEL

Research Fields

Growth and functionalization of Graphene – Engineering of Band Structure

D. Aubel, S. Hajjar-Garreau, M. Cranney, E. Denys, A. Florentin, F. Vonau et L. Simon*

*Contact : laurent.simon@uha.fr

Here we explore different ways to modify the electronic properties of Graphene and to obtain 2D heterostructures made of Graphene or MoS2 on various substrates. Using a multidisciplinary approach, we study the covalent grafting of molecules or their interactions with physisorbed self-assembled organic layers on these materials, with an emphasis on a possible modification of the Fermi level by charge transfer. Creation of functionalized defects or deposition followed by the intercalation of various elements (noble metals, lanthanides, etc.) have an impact on the physical properties of these 2D heterostructures too.

For these studies, we are depositing metals in UHV by sublimation and we have several means to deposit molecules in UHV : by molecular-beam epitaxy, by pulse-injection in liquid phase using a valve or by electrospray ion beam deposition (under development).

These UHV deposition chambers are connected to a low temperature Scanning Tunnelling Microscope (LT-STM) working up to 4K and to a UHV chamber dedicated to Photoelectron Spectroscopy measurements (XPS, ARPES) measurements using a VG Scienta R3000 spectrometer equipped with a hemispherical analyser and monochromatic x-ray and UV sources. We are then able to systematically study in situ the physico-chemical properties and the band structure (electronical properties) of our samples.

Reprinted with permission from Daukiya, L. ; Mattioli, C. ; Aubel, D. ; Hajjar-Garreau, S. ; Vonau, F. ; Denys, E. ; Reiter, G. ; Fransson, J. ; Bocquet, M.-L. ; Bena, C. ; Gourdon, A. ; Simon, L. Covalent Functionalization by Cycloaddition Reactions of Pristine Defect-Free Graphene. ACS Nano, 2017, 11, 627-634. Copyright 2017 American Chemical Society.

Publications :
L. Daukiya, M.N. Nair, S. Hajjar-Garreau, F. Vonau, D. Aubel, J.-L. Bubendorff, M. Cranney, E. Denys, A. Florentin, G. Reiter and L. Simon Phys. Rev. B 97 2018 035309 DOI : 10.1103/PhysRevB.97.035309
L. Daukiya, C. Mattioli, D. Aubel, S. Hajjar-Garreau, F. Vonau , E. Denys, G. Reiter, J. Fransson, E. Perrin, M.-L. Bocquet, C. Bena, A. Gourdon, and L. Simon ACS Nano 11 (1), 2017 pp 627–634  DOI : 10.1021/acsnano.6b06913
Nair, M. Narayanan, M. Cranney, T. Jiang, S. Hajjar-Garreau, D. Aubel, D. Aubel, F. Vonau, A. Florentin, E. Denys, M.-L Bocquet and L. Simon Phys. Rev. B 94 2016 075427 DOI : 10.1103/PhysRevB.94.075427
Hu Li, Lakshya Daukiya, Soumyajyoti Haldar, Andreas Lindblad,Biplab Sanyal, Olle Eriksson, Dominique Aubel, Samar Hajjar-Garreau, Laurent Simon and Klaus Leifer Nature scientific report, 6 2016, 19719 DOI : 10.1038/srep19719
Yu-Pu Lin, Y. Ksari, D. Aubel, S. Hajjar-Garreau, G. Borvon, Y. Spiegel, L. Roux, L. Simon and J.M. Themlin Carbon 100 (2016) 337.
F. M. N. Nair, M. Cranney, F. Vonau, D. Aubel, P. Le Fèvre, A. Tejeda, F. Bertran, A. Taleb-Ibrahimi and L. Simon Phys. Rev B 85 2012 245421 DOI : 10.1103/PhysRevB.85.245421

Synthesis and study of physical properties of supramolecular assemblies and 2D/3D monocrystals composed of π-conjugated molecules

F. Vonau, D. Aubel, M. Cranney, J.-L. Bubendorff, L. Simon*

*Contact : laurent.simon@uha.fr

Here we aim to understand how the structure and conformation of one molecule has an impact on the self-assembly process and on the internal organisation of supramolecular structures, which can be wires (1D), molecular layers (2D) or molecular crystals (3D), and whose sizes range from nm to mm. Periodicities in these structures, at the molecular scale to the mesoscopic scale, create new optical and electronical properties that we study and use in devices like OFET or new organic solar cells for example, in collaboration with international teams (ICube Laboratory in Strasbourg, the Albert-Ludwig University and the Fraunhofer Institute for Solar Energy, both in Freiburg, Germany).

For example, using STM/STS we evidenced a new and specific self-assembly mechanism of π-conjugated molecules on graphene, which enables charge delocalization along the self-assembled 1D supramolecular wire-like structures. Using these molecules, we were then able to grow supramolecular monocrystals of mesoscopic sizes, whose optical properties and electronical/transport properties have been studied.

Reprinted with permission from Shokri, R. ; Lacour, M.-A. ; Jarrosson, T. ; Lère-Porte, J.-P. ; Serein-Spirau, F. ; Miqueu, K. ; Sotiropoulos, J.-M. ; Vonau, F. ; Aubel, D. ; Cranney, M. ; Reiter, G. ; Simon, L. Generating Long Supramolecular Pathways with a Continuous Density of States by Physically Linking Conjugated Molecules via Their End Groups. J. Am. Chem. Soc., 2013, 135, 5693-5698. Copyright 2013 American Chemical Society.

Publications :
Wurfel, U., Sebastian Mackowskissler, M., Unmassig, M., Hofmann, N., List, M., Mankel, E., Mayer, T., Reiter, G., Bubendorff, J.-L., Simon, L. and Kohlstadt, M.   Adv. Energy Mater. 2016, 6, 1600594.DOI 10.1002/aenm.201600594
S. Motamen, C. Schörner, D. Raithel, J.-P. Malval, T. Jarrosson, F. Serein-Spirau, L. Simon, R. Hildner, G. Reiter PCCP 2017 19  15980 DOI : 10.1039/C7CP01639E
S. Motamen, D. Raithel, R. Hildner, K. Rahimi, T. Jarrosson, F. Serein-Spirau, L. Simon, and G. Reiter, ACS Photonics 2016  3, 2315 DOI : 1598010.1021/acsphotonics.6b00473
W. Hourani, K. Rahimi, I. Botiz, F. P. V. Koch, G. Reiter, P. Lienerth, T. Heiser, J.-L. Bubendorff and L. Simon, Nanoscale 2014, 6, 4774 (2014) DOI : 10.1039/c3nr05858a
F. Vonau, R. Shokri, D. Aubel, L. Bouteiller, O.A. Guskova, J.-U. Sommer, G. Reiter and L. Simon Nanoscale 2014, 6, 8250 DOI : 10.1039/C4NR00539B
R. Shokri, M.-A. Lacour, T. Jarrosson, J.-P. Lère-Porte, F. Serein-Spirau, K. Miqueu, J.-M. Sotiropoulos, F. Vonau, D. Aubel, M. Cranney, G. Reiter, and L. Simon, JACS 2013 135(15), 5693-5698  DOI : 10.1021/ja311964b

Growth and electronic structure of 2D crystals based on Si and Ge.

*Contact : carmelo.pirri@uha.fr

Publications :

K. Zhang, M.-C. Hanf, D. Sciacca, R. Bernard, Y. Borensztein, A. Resta, Y. Garreau, A. Vlad, A. Coati, I. Lefebvre, M. Derivaz, C. Pirri, P. Sonnet, R. Stephan, and G. Prévot Phys. Rev. B 106, 045412 2022 DOI : 10.1103/PhysRevB.106.045412
K. Zhang, D. Sciacca, M.-C. Hanf, R. Bernard, Y. Borensztein, A. Resta, Y. Garreau, A. Vlad, A. Coati, I. Lefebvre, M. Derivaz, C. Pirri, P. Sonnet, R. Stephan, and G. Prévot. Phys. Chem. C , 125 (44) 24702–24709 2021 DOI :10.1021/acs.jpcc.1c07585
K. Zhang, D. Sciacca, A. Coati, R. Bernard, Y. Borensztein, P. Diener, B. Grandidier, I. Lefebvre, M. Derivaz, C. Pirri, and G. Prévot Phys. Rev. B 104 , 155403 2021 DOI :10.1103/PhysRevB.104.155403
N. Massara, A. Marjaoui, R. Stephan, M-C Hanf, M. Derivaz, D. Dentel, S. Hajjar-Garreau, A. Mehdaoui, M. Diani, P. Sonnet and C. Pirri 2D Mater. 6 035016 2019 DOI : 10.1088/2053-1583/ab1601
R. Stephan, M. Derivaz, M.C. Hanf, D. Dentel, N. Massara, A. Mehdaoui, Ph. Sonnet, C. Pirri J. Phys. Chem. Lett. , 8 (18), 4587-4593 2017 DOI : 10.1021/acs.jpclett.7b02137
R. Stephan, M.C. Hanf, M. Derivaz, D. Dentel, M.C. Asensio, J. Avila, A. Mehdaoui, P. Sonnet, C. Pirri J. Phys. Chem. C, 120 (3), 1580-1585 2016 DOI :10.1021/acs.jpcc.5b10307
M. Derivaz, D. Dentel, R. Stephan, M.-C. Hanf, A. Mehdaoui, P. Sonnet, C. Pirri Nano Lett., 15(4), 2510-2516 2015 DOI :10.1021/acs.nanolett.5b00085

Growth of ultrathin semiconducting/insulating organic layers on ferromagnetic surfaces

G. Garreau*, S. Hajjar-Garreau, P. Wetzel

*Contact : guillaume.garreau@uha.fr

We focus on the growth and electronic properties of organic (a-C, phthalocyanines) monolayers that present highly spin-polarized interface states around the Fermi level after deposition on ferromagnetic surfaces.

Publications :
Djeghloul, F., Garreau, G., Gruber, M., Joly, L., Boukari, S., Arabski, J., Bulou, H., Scheurer, F., Hallal, A., Bertran, F., Le Fevre, P., Taleb-Ibrahimi, A., Wulfhekel, W., Beaurepaire, E., Hajjar-Garreau, S., Wetzel, P., Bowen, M. and Weber, W. Carbon 2015, 87, 269 DOI : 10.1016/j.carbon.2015.02.043
Djeghloul, F., Gruber, M., Urbain, E., Xenioti, D., Joly, L., Boukari, S., Arabski, J., Bulou, H., Scheurer, F., Bertran, F., Le Fevre, P., Taleb-Ibrahimi, A., Wulfhekel, W., Garreau, G., Hajjar-Garreau, S., Wetzel, P., Alouani, M., Beaurepaire, E., Bowen, M. and Weber, W. 2016 J. Phys. Chem. Lett.  7, 2310. DOI : 10.1021/acs.jpclett.6b01112

Specific facilities


Multi-purpose ultra-high vacuum systems with several complementary techniques of surface analysis : Scanning Tunnelling Microscopy (STM, LT-STM), Photoelectron Spectroscopy (XPS, UPS, ARPES), Electron Diffraction techniques (LEED, XPD).  These UHV systems are equipped with several deposition techniques, both for organic and inorganic products. Systematic studies of structural and electronic properties are then completed, both in the local (i.e. atomic scale) and in the global scale (i.e. mesoscopic scale).


We also use other instruments that work in ambient conditions, like Atomic Force Microscopes (conductive AFM, SKPFM), or a Scanning Tunnelling Microscope imaging at the solid-liquid interface.

Main collaborators

Université Albert Ludwig à Freiburg (Germany)

Laboratoire Angström Université d’Uppsala (Sweden)

CEMES Toulouse (France)

ENS-Paris département de Chimie (France)

Institut de Physique Théorique (Saclay, France)

Fraunhofer Institute for Solar Energy (Germany)

IPCMS Strasbourg (France)

Synchrotron SOLEIL (France)

Université d’Oran (Algeria)

CINAM Marseille (France)

Institut des Nanosciences de Paris (France)

Université de Tanger (Morocco)

ICGM Montpellier (France)