Publications de Pietro Gambardella

Correlation between Electronic Configuration and Magnetic Stability in Dysprosium Single Atom Magnets

Harald Brune, Stefano Rusponi, Marina Pivetta, Christian Wäckerlin, Jan Gui-Hyon Dreiser, Pietro Gambardella, Fabio Donati, Aparajita Singha, Romana Baltic, Edgar Fernandes

Single atom magnets offer the possibility of magnetic information storage in the most fundamental unit of matter. Identifying the parameters that control the stability of their magnetic states is crucial to design novel quantum magnets with tailored proper ...

AMER CHEMICAL SOC2021

Unconventional Spin Relaxation Involving Localized Vibrational Modes in Ho Single-Atom Magnets

Harald Brune, Stefano Rusponi, Marina Pivetta, Christian Wäckerlin, Jan Gui-Hyon Dreiser, Pietro Gambardella, Fabio Donati, Aparajita Singha, Romana Baltic, Katharina Johanna Diller

We investigate the spin relaxation of Ho single atom magnets on MgO/Ag(100) as a function of temperature and magnetic field. We find that the spin relaxation is thermally activated at low field, while it remains larger than 1000 s up to 30 K and 8 T. This ...

AMER PHYSICAL SOC2020

4 f occupancy and magnetism of rare-earth atoms adsorbed on metal substrates

Harald Brune, Stefano Rusponi, Jan Gui-Hyon Dreiser, Christian Wäckerlin, Pietro Gambardella, Fabio Donati, Aparajita Singha, Romana Baltic, Sebastian Stepanow

We report x-ray absorption spectroscopy and x-ray magnetic circular dichroism measurements as well as multiplet calculations for Dy, Ho, Er, and Tm atoms adsorbed on Pt(111), Cu(111), Ag(100), and Ag(111). In the gas phase, all four elements are divalent a ...

Amer Physical Soc2017

Complex Magnetic Exchange Coupling between Co Nanostructures and Ni(111) across Epitaxial Graphene

Harald Brune, François Patthey, Stefano Rusponi, Marina Pivetta, Pietro Gambardella, Fabio Donati

We report on the magnetic coupling between isolated Co atoms as well as small Co islands and Ni(111) mediated by an epitaxial graphene layer. X-ray magnetic circular dichroism and scanning tunneling microscopy combined with density functional theory calcul ...

American Chemical Society2016

Magnetic remanence in single atoms

Harald Brune, François Patthey, Stefano Rusponi, Christian Wäckerlin, Jan Gui-Hyon Dreiser, Pietro Gambardella, Fabio Donati, Zeljko Sljivancanin, Aparajita Singha, Romana Baltic

A permanent magnet retains a substantial fraction of its saturation magnetization in the absence of an external magnetic field. Realizing magnetic remanence in a single atom allows for storing and processing information in the smallest unit of matter. We s ...

American Association for the Advancement of Science2016

Origin of Perpendicular Magnetic Anisotropy and Large Orbital Moment in Fe Atoms on MgO

Harald Brune, Stefano Rusponi, Marina Pivetta, Jan Gui-Hyon Dreiser, Pietro Gambardella, Fabio Donati, Luca Gragnaniello, Giulia Elisabetta Pacchioni

We report on the magnetic properties of individual Fe atoms deposited on MgO(100) thin films probed by x-ray magnetic circular dichroism and scanning tunneling spectroscopy. We show that the Fe atoms have strong perpendicular magnetic anisotropy with a zer ...

American Physical Society2015

Magnetic Moment and Anisotropy of Individual Co Atoms on Graphene

Harald Brune, Oleg Yazyev, François Patthey, Pietro Gambardella, Fabio Donati, Gabriel Albert Autes, Quentin Dubout

We report on the magnetic properties of single Co atoms on graphene on Pt(111). By means of scanning tunneling microscopy spin-excitation spectroscopy, we infer a magnetic anisotropy of K = -8.1 meV with out-of-plane hard axis and a magnetic moment of 2.2 ...

American Physical Society2013

Oxygen Dissociation by Concerted Action of Di-Iron Centers in Metal-Organic Coordination Networks at Surfaces: Modeling Non-Heme Iron Enzymes

Klaus Kern, Pietro Gambardella, Sebastian Stepanow, Alexandre Dmitriev

The high chemical reactivity of unsaturated metal sites is a key factor for the development of novel devices with applications in sensor engineering and catalysis. It is also central in the research for sustainable energy concepts, e.g., the efficient prod ...

American Chemical Society (ACS)2011

Self-Assembled Nanometer-Scale Magnetic Networks on Surfaces: Fundamental Interactions and Functional Properties

Klaus Kern, Harald Brune, Stefano Rusponi, Pietro Gambardella, Anne Lehnert, Sergio Vlaic, Sebastian Stepanow

Nanomagnets of controlled size, organized into regular patterns open new perspectives in the fields of nanoelectronics, spintronics, and quantum computation. Self-assembling processes on various types of substrates allow designing fine-structured architect ...

Wiley-Blackwell2011

Spin and Orbital Magnetic Moment Anisotropies of Monodispersed Bis(Phthalocyaninato)Terbium on a Copper Surface

Klaus Kern, Pietro Gambardella, Stephan Rauschenbach, Sebastian Stepanow, Tzu-Chun Tseng, Violetta Sessi, Nasiba Abdurakhmanova

The magnetic properties of isolated TbPc2 molecules supported on a Cu(100) surface are investigated by X-ray magnetic circular dichroism at 8 K in magnetic fields up to 5 T. The crystal field and magnetic properties of single molecules are found to be robu ...

2010