Skip to main content
  • Paul Scherrer Institut PSI
  • PSI Research, Labs & User Services

Digital User Office

  • Digital User Office
  • DE
  • EN
  • FR
Paul Scherrer Institut (PSI)
Search
Paul Scherrer Institut (PSI)

Hauptnavigation

  • Research at PSIOpen mainmenu item
    • Research Initiatives
    • Ethics and Research integrity
    • Scientific Highlights
    • Scientific Events
    • Scientific Career
    • PSI-FELLOW
    • PSI Data Policy
  • Research Divisions and LabsOpen mainmenu item
    • Overview
    • Research with Neutrons and Muons
    • Photon Science
    • Energy and Environment
    • Nuclear Energy and Safety
    • Biology and Chemistry
    • Scientific Computing, Theory and Data
    • Large Research Facilities
  • Facilities and InstrumentsOpen mainmenu item
    • Overview
    • Large Research Facilities
    • Facilities
    • PSI Facility Newsletter
  • PSI User ServicesOpen mainmenu item
    • User Office
    • Methods at the PSI User Facilities
    • Proposals for beam time
    • Proposal Deadlines
    • Data Analysis Service (PSD)
    • EU support programmes
  • New ProjectsOpen mainmenu item
    • SLS 2.0
    • IMPACT
  • DE
  • EN
  • FR

Digital User Office (mobile)

  • Digital User Office

You are here:

  1. PSI Home
  2. Labs & User Services
  3. PSD
  4. LXN
  5. Research Groups
  6. Molecular Nanoscience
  7. Spins in Molecular Monolayers

Secondary navigation

Laboratory for X-ray Nanoscience and Technologies (LXN)

  • About LXN
    • Organisational Structure
  • Open Positions
  • People
  • Research Groups Expanded submenu item
    • X-ray Nano-Optics
      • X-ray Optics for Imaging and Spectroscopy
        • Fresnel Zone Plate for X-ray Microscopy
        • Blazed X-ray Optics
        • Zernike X-ray Phase Contrast Microscopy
        • Fresnel Zone Plates for RIXS
        • Refractive Lenses by 2 Photon 3D Lithography
      • Wavefront Metrology and Manipulation
        • Vortex Fresnel Zone Plates
        • Grating-based Wavefront Metrology
      • X-ray Optics for XFELs
        • Diamond Fresnel Zone Plates
        • Beam Splitter Gratings for Spectral Monitoring
        • A Delay Line for Ultrafast Pump-Probe Experiments
        • X-ray Streaking for Ultrafast Processes
    • Molecular Nanoscience Expanded submenu item
      • On-surface Chemistry
      • Spins in Molecular Monolayers
      • SiC: Surfaces and Interfaces
      • Our Research Team
    • Advanced Lithography and Metrology
      • EUV Interference Lithography
      • EUV Lensless Imaging
      • ALM Nanoscience
    • Quantum Photon Science
      • News and highlights
      • People
      • Open positions
      • Current projects
        • Imaging quantum many-body states
        • Nonlinear magnonics
        • Optical devices & methods
        • Rare-earth quantum magnets
        • Rydberg states in Si ∂-layers
        • Strained Ge laser (former research activity of H. Sigg & collaborators)
        • Van der Waals materials & devices
      • Infrastructure
        • Cristallina-Q
        • IR beamline
        • Nano-fabrication
      • Publications
      • QTC@PSI
    • Detectors
      • Projects
        • MYTHEN
        • GOTTHARD
        • EIGER
        • JUNGFRAU
        • MOENCH
        • AGIPD
        • Documentation
        • Software Releases
      • Research
      • Detectors Scientific Highlights
      • Publications
      • Team
  • Facilities and Equipment
    • Surface Science Lab
    • Scanning Electron Microscopy
    • Scanning Probe Microscopy
    • PEARL Beamline
    • XIL Facility at the SLS
    • Cleanroom Labs
  • Scientific Highlights and News
    • Archive
  • Publications
    • Archive

Quantum Wells and Spin in Supramolecular Architectures

The possibility to use organic compounds at surfaces to create specific, also low-dimensional architectures containing quantum wells and spin bearing atoms opens up new opportunities. This in particular as they allow for the programming of the assembly and for the often-precise modification of their properties by chemical substitution. To advance towards versatile quantum materials and to explore future quantum devices with decreasing characteristic dimension and increasingly well-defined contacts/gates the understanding of the electronic and magnetic coupling within these architectures is of utmost importance.

Fig.1 STM (top) and XAS/XMCD (bottom) data of MnTPPCl (Mn tetraphenylporphyrin chloride) sublimed onto Co (left) and onto oxygen-reconstructed Co (right). In case of MnTPPCl on Co, the XMCD evidences a ferromagnetic coupling between the substrate (Co) and the Mn in the molecule. MnTPPCl on O/Co however, is antiferromagnetically coupled to the substrate.
Fig.1 STM (top) and XAS/XMCD (bottom) data of MnTPPCl (Mn tetraphenylporphyrin chloride) sublimed onto Co (left) and onto oxygen-reconstructed Co (right). In case of MnTPPCl on Co, the XMCD evidences a ferromagnetic coupling between the substrate (Co) and the Mn in the molecule. MnTPPCl on O/Co however, is antiferromagnetically coupled to the substrate.
Fig. 2 XAS/XMCD showing the different novel magnetochemical effects observed on surface: 'spin on' to 'spin off', 'spin high' to 'spin low', 'spin FM' to 'spin AFM' and 'coupling strong' to 'coupling weak'.
Fig. 2 XAS/XMCD showing the different novel magnetochemical effects observed on surface: 'spin on' to 'spin off', 'spin high' to 'spin low', 'spin FM' to 'spin AFM' and 'coupling strong' to 'coupling weak'.
XMCD.png

Our pioneering work showed that monolayers of organic paramagnetic molecules can couple both ferromagnetically [1, 2] and antifer‐ romagnetically [3] to the underlying ferromagnetic surfaces depend‐ ing on their electronic structure. If sublimed onto an oxygen‐ reconstructed ferromagnetic substrate, the molecules are coupled antiferromagnetically with respect to the substrate [4]. Furthermore, we find that the oxygen‐reconstruction allows for the self‐assembly of the ad‐molecules. This recipe has been used to create the first 2 dimensional ferrimagnetic sheet as proven by T-dependent X-ray magnetic circular dichroism experiments at the Swiss Light Source and complementary Scanning Tunneling Microscopy/Spectroscy at varied  low Temperatures [6].

The magnetic moments in the ad‐molecules and in the ferromag‐ netic substrates are determined by the element specific X‐ray mag‐ netic circular dichoism (XMCD) technique. The XMCD experiments are performed at the Swiss Light Source (SLS) in collaboration with the Microscopy and Magnetism Group on samples which are pre‐ pared and characterized in our Surface Science Lab. Thus, we employ a combination of local (Scanning Tunneling Microscopy) with spatially averaging (X‐ray photoelec‐ tron spectroscopy, X‐ray absorption, XMCD) techniques. The experiments are complemented by den‐ sity functional theory (DFT+U) calculations performed by Peter Oppeneer and co‐workers (University of Uppsala). On the basis of possibility to induce a magnetic moment into molecular complexes, we explore the "spin off" [5].

We find that, if applied to those on‐surface complexes, coordination of the external stimulus can also

i) tune the spin ("spin high" to "spin low"), ii) change the sign of the exchange coupling ("spin FM" to spin "AFM") and iii) adjust the strength of the exchange coupling ("coupling strong" to "coupling weak"). In consequence to the "trans effect", we the observed magnetochemical effects provide evi‐ dence for the existence of a "surface spin trans effect".

 

Publications

[1] Induced magnetic ordering in a molecular monolayer
A. Scheybal, T. Ramsvik, R. Bertschinger, M. Putero, F. Nolting, et al.
Chem. Phys. Lett. 411, 214 (2005)

[2] Indirect magnetic coupling of manganese porphyrin to a ferromagnetic cobalt substrate
D. Chylarecka, T. K. Kim, K. Tarafder, K. Müller, K. Gödel, et al.
J. Phys. Chem. C 115, 1295 (2011)

[3] Antiferromagnetic coupling of Cr-porphyrin to a bare Co substrate
J. Girovsky, K. Tarafder, C. Waeckerlin, J. Nowakowski, D. Siewert et al.
Phys. Rev. B 90, 220404 (2014)

[4] Self-assembly and superexchange coupling of magnetic molecules on oxygen-reconstructed ferromagnetic thin film
D. Chylarecka, C. Wäckerlin, T. K. Kim, K. Müller, F. Nolting, et al.
J. Phys. Chem. Lett. 1, 1408 (2010)

[5] Controlling spins in adsorbed molecules by a chemical switch
C. Wäckerlin, D. Chylarecka, A. Kleibert, K. Müller, C. Iacovita, et al.
Nature Comm. 1, 61 (2010)

[6]   Long-range ferrimagnetic order in atwo-dimensional supramolecular Kondo lattice
J. Girovsky et al,

 Nature Comm. 10.1038/ncomms (2017)

[7] On-surface coordination chemistry of planar molecular spin systems: novel magnetochemical effects induced by axial ligands
C. Wäckerlin, K. Tarafder, D. Siewert, J. Girovsky, T. Hählen, et al.
Chem. Sci. doi:10.1039/c2sc20828h (2012)

Sidebar

Contact

Prof. Thomas Jung

Laboratory for Molecular Nanoscience
Paul Scherrer Institut
5232 Villigen PSI
Switzerland

Telephone: +41 56 310 45 18
E-mail: thomas.jung@psi.ch

top

Footer

Paul Scherrer Institut

Forschungsstrasse 111
5232 Villigen PSI
Switzerland

Telephone: +41 56 310 21 11
Telefax: +41 56 310 21 99

How to find us
Contact

Visitor Centre psi forum
School Lab iLab (in German)
Center for Proton Therapy
PSI Education Centre
PSI Guest House
PSI Gastronomie (in German)
psi forum shop

Service & Support

  • Phone Book
  • User Office
  • Accelerator Status
  • PSI Publications
  • Suppliers
  • E-Billing
  • Computing
  • Safety (in German)

Career

  • Working at PSI
  • Job Opportunities
  • Training and further education
  • Career Center
  • Vocational Training (in German)
  • PSI Education Center

For the media

  • PSI in brief
  • Facts and Figures
  • Media corner
  • Media Releases
  • Social Media

Follow us: Twitter (in English) LinkedIn Youtube Facebook Instagram Issuu RSS

Footer legal

  • Imprint
  • Terms and Conditions
  • Editors' login