Publications de Violetta Sessi

Modeling Ferro- and Antiferromagnetic Interactions in Metal-Organic Coordination Networks

Klaus Kern, Sebastian Stepanow, Tzu-Chun Tseng, Violetta Sessi, Alexander Langner, Nasiba Abdurakhmanova, Christopher Seiji Kley

Magnetization curves of two rectangular metalorganic coordination networks formed by the organic ligand TCNQ (7,7,8,8-tetracyanoquinodimethane) and two different (Mn and Ni) 3d transition metal atoms [M(3d)] show marked differences that are explained using ...

Amer Chemical Soc2015

Complex trend of magnetic order in Fe clusters on 4d transition-metal surfaces. I. Experimental evidence and Monte Carlo simulations

Klaus Kern, Violetta Sessi

We demonstrate the occurrence of compensated spin configurations in Fe clusters and monolayers on Ru(0001) and Rh(111) by a combination of x-ray magnetic circular dichroism experiments, first-principles calculations, and Monte Carlo simulations. Our result ...

Amer Physical Soc2014

Superexchange-Mediated Ferromagnetic Coupling in Two-Dimensional Ni-TCNQ Networks on Metal Surfaces

Klaus Kern, Tzu-Chun Tseng, Violetta Sessi, Nasiba Abdurakhmanova, Christopher Seiji Kley

We investigate the magnetic coupling of Ni centers embedded in two-dimensional metal-coordination networks self-assembled from 7,7,8,8-tetracyanoquinodimethane (TCNQ) molecules on Ag(100) and Au (111) surfaces. X-ray magnetic circular dichroism measurement ...

Amer Physical Soc2013

In-Plane Magnetic Anisotropy of Fe Atoms on Bi2Se3(111)

Klaus Kern, Violetta Sessi

The robustness of the gapless topological surface state hosted by a 3D topological insulator against perturbations of magnetic origin has been the focus of recent investigations. We present a comprehensive study of the magnetic properties of Fe impurities ...

2012

Coordination dependent magnetic properties of 3d and 4d metal nano-structures

Violetta Sessi

In this thesis, the magnetic properties of self-assembled 3d and 4d metal nano-structures supported on surfaces have been investigated. The atomic coordination within the nano-structures was found to profoundly affect important quantities such as the magne ...

EPFL2010

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

Electronic decoupling and templating of Co nanocluster arrays on the boron nitride nanomesh

Klaus Kern, Jian Zhang, Violetta Sessi

Positioning nanostructures and functional molecules at surfaces and engineering their local coupling behavior is a key challenge in nanotechnology. The recently discovered BN nanomesh on the Rh(111) surface is a potential candidate to combine both properti ...

2008

Structure and magnetism of atomically thin Fe layers on flat and vicinal Pt surfaces

Klaus Kern, Harald Brune, Stefano Rusponi, Pietro Gambardella, Violetta Sessi

Ultrathin Fe films on Pt substrates have been investigated under ultrahigh vacuum conditions by scanning tunneling microscopy, low energy electron diffraction, magneto-optical Kerr effect, x-ray magnetic circular dichroism measurements, and Kerr microscopy ...

2006