Publications de Jan Gui-Hyon Dreiser

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

Island formation of Er(trensal) single-ion magnets on graphene observed on the micrometer scale

Christian Wäckerlin, Jan Gui-Hyon Dreiser

We have studied the morphology of Er(trensal) single-ion molecular magnets adsorbed on graphene/Ru(0001) using X-ray photoemission electron microscopy (X-PEEM). By exploiting the elemental contrast at the erbium M-5 edge we observe the formation of molecul ...

2021

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

Magnetic properties of on-surface synthesized single-ion molecular magnets

Harald Brune, Stefano Rusponi, Marina Pivetta, Christian Wäckerlin, Jan Gui-Hyon Dreiser, Aparajita Singha, Katharina Johanna Diller

We perform on-surface synthesis of single-ion molecular magnets on an Ag(111) surface and characterize their morphology, chemistry, and magnetism. The first molecule we synthesize is TbPc2 to enable comparison with chemically synthesized and subsequently s ...

2019

Large effect of metal substrate on magnetic anisotropy of Co on hexagonal boron nitride

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

We combine x-ray absorption spectroscopy (XAS), x-raymagnetic circular dichroism (XMCD) and x-ray magnetic linear dichroism (XMLD) data with first principles density functional theory (DFT) calculations and amultiorbital many-body Hamiltonian approach to u ...

2019

Understanding the Superior Stability of Single-Molecule Magnets on an Oxide Film

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

The stability of magnetic information stored in surface adsorbed single-molecule magnets is of critical interest for applications in nanoscale data storage or quantum computing. The present study combines X-ray magnetic circular dichroism, density function ...

2019

Magnetic properties of single rare-earth atoms on graphene/Ir(111)

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

2018

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

Magnetic Hysteresis in Er Trimers on Cu(111)

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

We report magnetic hysteresis in Er clusters on. Cu(111) starting from the size-of three atoms. combining Xray magnetic circular dichroism, scanning tunneling microscopy, and mean-field nucleation theory, we determine the size dependent magnetic properties ...

American Chemical Society2016

Out-of-Plane Alignment of Er(trensal) Easy Magnetization Axes Using Graphene

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

We have studied Er(trensal) single -ion magnets adsorbed on graphene/Ru(0001), on graphene/Ir(111), and on bare Ru(0001) by scanning tunneling microscopy and X-ray absorption spectroscopy. On graphene, the molecules self -assemble into dense and well -orde ...

American Chemical Society2016