Publications de Peter Wahl | EPFL Graph Search

Controlling Single Molecule Conductance by a Locally Induced Chemical Reaction on Individual Thiophene Units

Klaus Kern, Uta Schlickum, Peter Wahl, Hagen Klauk, Ivan Pentegov, Verena Katharina Schendel

Among the prerequisites for the progress of single-molecule-based electronic devices are a better understanding of the electronic properties at the individual molecular level and the development of methods to tune the charge transport through molecular jun ...

Wiley-VCH Verlag GmbH2020

Remotely Controlled Isomer Selective Molecular Switching

Klaus Kern, Uta Schlickum, Peter Wahl, Hagen Klauk, Ivan Pentegov, Verena Katharina Schendel

Non local addressing-the "remote control"- of molecular switches promises more efficient processing for information technology, where fast speed of switching is essential. The surface state of the (111) facets of noble metals, a confined two-dimensional el ...

Amer Chemical Soc2016

Bipolar Conductance Switching of Single Anthradithiophene Molecules

Klaus Kern, Uta Schlickum, Peter Wahl, Hagen Klauk, Ivan Pentegov, Verena Katharina Schendel

Single molecular switches are basic device elements in organic electronics. The pentacene analogue anthradithiophene (ADT) shows a fully reversible binary switching between different adsorption conformations on a metallic surface accompanied by a charge tr ...

Amer Chemical Soc2015

Temperature and magnetic field dependence of a Kondo system in the weak coupling regime

Klaus Kern, Markus Ternes, Uta Schlickum, Peter Wahl

The Kondo effect arises due to the interaction between a localized spin and the electrons of a surrounding host. Studies of individual magnetic impurities by scanning tunneling spectroscopy have renewed interest in Kondo physics; however, a quantitative co ...

Nature Publishing Group2013

Quantum transport through single atoms and molecules

Klaus Kern, Peter Wahl, Yi Zhang

Experiments on quantum transport in a low temperature scanning tunneling microscope provide the possibility to study atomic and molecular contacts with well-defined electrode-geometry at least for one of the contacts, the surface. Here, we show for a numbe ...

Wiley-V C H Verlag Gmbh2013

Experimental visualization of scattering at defects in electronic transport through a single atomic junction

Klaus Kern, Peter Wahl

For electronic transport at the nanoscale, coherent scattering at defects plays an important role. Therefore, the capability of visualizing the influence of defects on the conductivity of single atomic junctions may benefit the development of future nano-e ...

Amer Physical Soc2013

Local spectroscopy of the Kondo lattice YbAl3: Seeing beyond the surface with scanning tunneling microscopy and spectroscopy

Klaus Kern, Peter Wahl

We report on an atomic-scale study of the Kondo lattice compound YbAl3 using scanning tunneling microscopy (STM) and spectroscopy (STS). An analysis of the surface orientation and structure is performed based on STM images containing more than one crystal ...

2011

Quantum Point Contact Microscopy

Klaus Kern, Peter Wahl

We introduce quantum point contact microscopy (QPCM) as a novel method for surface characterization, where the conductance through a quantum point contact formed by a metal atom between the tip of a scanning tunneling microscope and the surface is mapped a ...

American Chemical Society (ACS)2011

A tunable two-impurity Kondo system in an atomic point contact

Klaus Kern, Peter Wahl

Two magnetic atoms, one attached to the tip of a scanning tunnelling microscope and one adsorbed on a metal surface, each constituting a Kondo system, have been proposed as one of the simplest conceivable systems potentially exhibiting quantum critical beh ...

2011

Kondo-effect of substitutional cobalt impurities at copper surfaces

Klaus Kern, Peter Wahl

The influence of the coordination on the Kondo temperature of a magnetic impurity at a noble metal surface and the line shape observed in low temperature scanning tunneling spectroscopy (STS) is investigated for single cobalt atoms adsorbed on and embedded ...

2009

Potential energy landscape of metallic Moire patterns

Klaus Kern, Peter Wahl

The modulation of the electronic structure of cobalt islands on Cu(111) by the Moire pattern of an Ag overlayer is investigated. Acquisition of tunneling spectroscopy maps reveals a local modification of both the energy and the amplitude of the cobalt-rela ...

2009

Background removal in scanning tunneling spectroscopy of single atoms and molecules on metal surfaces

Klaus Kern, Peter Wahl

Scanning tunneling spectroscopy has developed into a powerful spectroscopic technique that has found wide application in the atomic scale characterization of the electronic properties of clean surfaces as well as adsorbates and defects at surfaces. However ...

2008

Local detection of spin-orbit splitting by scanning tunneling spectroscopy

Klaus Kern, Marco Grioni, Daniela Pacilè, Luca Moreschini, Peter Wahl

We demonstrate that the spin-orbit coupling of two-dimensional surface states can be detected locally by scanning-tunneling spectroscopy (STS). The spin splitting of the surface state induces a singularity in the local density of states which can be detect ...

2007