Publications de Harald Brune | EPFL Graph Search

Direct Electrical Access to the Spin Manifolds of Individual Lanthanide Atoms

Lanthanide atoms show long magnetic lifetimes because of their strongly localized 4f electrons, but electrical control of their spins has been difficult because of their closed valence shell configurations. We achieved electron spin resonance of individual ...

AMER CHEMICAL SOC2025

A high bandwidth and high transmission STM bias line for ESR and quantum stochastic resonance measurements at 0.4 K

Harald Brune, François Patthey, Clément Marie Soulard, Shixuan Shan, Johannes Schwenk

We present a scanning tunneling microscope operating in a 3He cryostat at a base temperature of 0.4 K, suitable for electron spin resonance (ESR) [S. Baumann, W. Paul, T. Choi, C. P. Lutz, A. Ardavan, and A. J. Heinrich, Science 350, 417 (2015)], quantum s ...

2025

Large Area Monolayer Graphene Transfer in Ultra-High Vacuum

Harald Brune, Stefano Rusponi, Darius Constantin Merk

Graphene transfer methods either employ support layers that have to be removed after transfer, giving rise to impurities, or are based on delamination from bulk crystals, yielding only small flakes with various thicknesses. We present a graphene transfer m ...

American Chemical Society (ACS)2025

CO Adsorption on a Single-Atom Catalyst Stably Embedded in Graphene

Harald Brune

Confined single metal atoms in graphene-based materials have proven to be excellent catalysts for several reactions and promising gas sensing systems. However, whether the chemical activity arises from the specific type of metal atom or is a direct consequ ...

2025

Electrically driven spin resonance of 4f electrons in a single atom on a surface

Harald Brune

A pivotal challenge in quantum technologies lies in reconciling long coherence times with efficient manipulation of the quantum states of a system. Lanthanide atoms, with their well-localized 4f electrons, emerge as a promising solution to this dilemma if ...

Nature Research2024

Reverse Spillover Dominating CO Adsorption on Single Cobalt Atoms in Graphene Divacancies

Harald Brune

The kinetics of molecular adsorption and desorption can unveil the details of the adsorption potential that impact, for instance, the overall sticking probability. This information is of particular importance for catalysis and gas sensing. We investigate t ...

2024

Probing Catalytic Sites and Adsorbate Spillover on Ultrathin FeO2-x Film on Ir(111) during CO Oxidation

Harald Brune, Hao Yin, Wei Fang

The spatially resolved identification of active sites on the heterogeneous catalyst surface is an essential step toward directly visualizing a catalytic reaction with atomic scale. To date, ferrous centers on platinum group metals have shown promising pote ...

Amer Chemical Soc2024

Element-specific X-Ray detection of electron paramagnetic resonance in thin films of quantum bits

Harald Brune, Giovanni Boero, Stefano Rusponi

Element-specific magnetism accessible by synchrotron-based X-ray spectroscopy has proven to be valuable to study spin and orbital moments of transition metals and lanthanides in technologically relevant thin-film and monolayer samples. The access to cohere ...

Nature Research2024

The Impact of Lattice Distortions on the Magnetic Stability of Single Atoms: Dy and Ho on BaO(100)

Harald Brune, Stefano Rusponi, Marina Pivetta, Darius Constantin Merk, Sébastien Reynaud, Boris Sorokin

X-ray magnetic circular dichroism, atomic multiplet simulations, and density functional theory calculations are employed to identify criteria for the optimum combination of supporting alkaline earth oxide and adsorption site maximizing the spin lifetimes o ...

WILEY-V C H VERLAG GMBH2023

Erbium and thulium on MgO(100)/Ag(100) as candidates for single atom qubits

Harald Brune, François Patthey, Stefano Rusponi, Marina Pivetta, Edgar Fernandes, Fabio Donati, Aparajita Singha

Lanthanide atoms on surfaces are an exceptional platform for atomic-scale magnetic information storage. However, their potential as qubits remains unexplored due to the limited number of experimental setups that can coherently drive the spins of single ada ...

AMER PHYSICAL SOC2023

Valence Orbitals Driving the Spin Dynamics in a Rare-Earth Single-Atom Magnet

Harald Brune, François Patthey, Stefano Rusponi, Marina Pivetta, Dante Philippe Sblendorio, Alberto Curcella

We combine spin-polarized scanning tunneling microscopy with quantum master equation analysis to investigate the spin dynamics of the single atom magnet Dy on graphene/Ir(111). By performing reading and writing experiments, we show that the strongly spin p ...

AMER PHYSICAL SOC2023

Highly Ordered and Thermally Stable FeRh Cluster Superlattice on Graphene for Low-Temperature Catalytic CO Oxidation

Harald Brune, Jean-Guillaume De Groot, Hao Yin

We report on bimetallic FeRh clusters with a narrow size-distribution grown on graphene on Ir(111) as a carbon-supported model catalyst to promote low-temperature catalytic CO oxidation. By combining scanning tunneling microscopy with catalytic performance ...

WILEY-V C H VERLAG GMBH2022

Increasing Magnetic Anisotropy in Bimetallic Nanoislands Grown on fcc(111) Metal Surfaces

Harald Brune, Stefano Rusponi, Sergio Vlaic, Dimitrios Mousadakos

The magnetic properties and the atomic scale morphology of bimetallic two-dimensional nanoislands, epitaxially grown on fcc(111) metal surfaces, have been studied by means of Magneto-Optical Kerr Effect and Scanning Tunneling Microscopy. We investigate the ...

MDPI2022

Slow Magnetic Relaxation of Dy Adatoms with In-Plane Magnetic Anisotropy on a Two- Dimensional Electron Gas

Harald Brune, Stefano Rusponi, Marina Pivetta, Darius Constantin Merk, Sébastien Reynaud, Boris Sorokin, Dante Philippe Sblendorio

We report on the magnetic properties of Dy atoms adsorbed on the (001) surface of SrTiO3. X-ray magnetic circular dichroism reveals slow relaxation of the Dy magnetization on a time scale of about 800 s at 2.5 K, unusually associated with an easy-plane mag ...

AMER CHEMICAL SOC2022

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

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

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

Asymmetric azide-alkyne Huisgen cycloaddition on chiral metal surfaces

Harald Brune, Roland Widmer, Roland Hany, Michael Bauer, Samuel Thomas Stolz

Achieving fundamental understanding of enantioselective heterogeneous synthesis is marred by the permanent presence of multitudinous arrangements of catalytically active sites in real catalysts. In this study, we address this issue by using structurally co ...

NATURE RESEARCH2021

Engineering atomic-scale magnetic fields by dysprosium single atom magnets

Harald Brune, Tobias Bilgeri

Atomic scale engineering of magnetic fields is a key ingredient for miniaturizing quantum devices and precision control of quantum systems. This requires a unique combination of magnetic stability and spin-manipulation capabilities. Surface-supported singl ...

Nature Portfolio2021

Asymmetric Elimination Reaction on Chiral Metal Surfaces

Harald Brune, Roland Widmer, Samuel Thomas Stolz, Martina Danese, Daniele Passerone

The production of enantiopure materials and molecules is of uttermost relevance in research and industry in numerous contexts, ranging from nonlinear optics to asymmetric synthesis. In the context of the latter, dehalogenation, which is an essential reacti ...

Wiley-V C H Verlag Gmbh2021

Mapping Orbital-Resolved Magnetism in Single Lanthanide Atoms

Harald Brune, Stefano Rusponi, Marina Pivetta, Fabio Donati, Aparajita Singha

Single lanthanide atoms and molecules are promising candidates for atomic data storage and quantum logic due to the long lifetime of their magnetic quantum states. Accessing and controlling these states through electrical transport requires precise knowled ...

AMER CHEMICAL SOC2021

Molecular motor crossing the frontier of classical to quantum tunneling motion

Harald Brune, Jan Prinz, Roland Widmer, Samuel Thomas Stolz

The reliability by which molecular motor proteins convert undirected energy input into directed motion or transport has inspired the design of innumerable artificial molecular motors. We have realized and investigated an artificial molecular motor applying ...

National Academy of Sciences2020