Coming Visitors and Research Stays:

Franziska Rüttger

Academic Affiliation: University of Göttingen

Skills and Expertise: NMR Spectroscopy, Nuclear Magnetic Resonance ,NMR Structure Elucidation, Mass Spectrometry, Structure Elucidation

Georg Traeger

Academic Affiliation: University of Gottingen

Research focus: Examination of 1D Coupled Peierls Chains on Si(111) using Scanning Tunneling Microscopy and Scanning Tunneling Spectroscopy

Mireia Tena Zuazolacigorraga

Academic Affiliation: Centro de Fisica de Materiales

Deung Jang Choi

Academic Affiliation: Centro de Fisica de Materiales

Expertise: Condensed matter physics, Magnetism, Superconductivity, SPM

Sebastian Loth

Affiliation: University of Stuttgart

Research interests: Nanoscience, Quantum Magnetism, Spin Dynamics, Correlated-Electron Materials, Scanning Tunneling Microscopy

Kirsten von Bergmann

Academic Affiliation: Universität Hamburg

Research interests: STM, magnetism, skyrmions, surfaces, spintronics

Matthias Bode

Academic Affiliation: University of Würzburg

Research interests: Solid-State Physics

Katja Becker

President of DFG, German Research Foundation

Affiliation: DFG, German Research Foundation

Maki Kawai

Affiliation: Institute for Molecular Science, National Institutes of Natural Sciences (NINS)

Research interests: Surface Science

Laëtitia Farinacci

Academic Affiliation: Freie Universität Berlin

Michele Capra

Academic Affiliation: Politecnico di Milano

Principal subjects: Solid state physics, Surface physics, Plasma physics, Photonics, Low dimensional systems, Electronics, Computer science

Maria Spethmann

Affiliation: University of Basel

Title: High-fidelity two-qubit gates of hybrid superconducting-semiconducting singlet-triplet qubits

Abstract:

Hybrid systems comprising superconducting and semiconducting materials are promising architectures for quantum computing. Superconductors induce interactions between the spin degrees of freedom of semiconducting quantum dots, based on crossed Andreev processes. In the talk I will present our theory where we show that these interactions are widely anisotropic when the semiconductor material has strong spin-orbit interactions. This anisotropy is tunable and enables fast and high-fidelity two-qubit gates between singlet-triplet spin qubits. The reason is that the design is immune to leakage into non-computational states and removes always-on  interactions between the qubits (crosstalk). We estimate two-qubit gate fidelities exceeding 99.9% without fine-tuning of parameters.

Daniel Kyungdeock Park

Academic Affiliation: Yonsei University

Title: Quantum machine learning: opportunities and challenges

Abstract:

Quantum computing has the potential to outperform any foreseeable classical computers for solving certain computational problems. With the growing demand for advanced computing power and methods in big data and artificial intelligence, quantum machine learning (QML) has emerged as one of the most exciting applications of quantum computing. In its early developments, QML gathered much attention mainly due to the quantum algorithm that solves the system of linear equations exponentially faster than its classical counterpart. However, this algorithm requires a fault-tolerant quantum computer and a quantum random access memory, which remain long-term prospect. Thus an important and challenging question is how noisy intermediate-scale quantum (NISQ) computers that are within reach can be utilized for QML. In this talk, I will first briefly introduce quantum machine learning. Then I will present several QML approaches that aim to utilize NISQ to the full extent and attain quantum advantages in the near future.

Joseph A Stroscio

Academic Affiliation: National Institute of Standards and Technology

Group: Nanoscale Processes and Measurements Group

Eric Switzer

Academic Affiliation: University of Central Florida

Specialization: Theoretical and Mathematical Physics

Clément Cabanetos

Academic Affiliation: University of Angers

Title: “Sooner or later, everything old is new again”: Functionalization and use of a forgotten dye

Abstract:

Abstract: Since the advent of organic electronics, various classes of π-conjugated molecular and macromolecular semiconductors have been reported. Among them, imide-containing rylenes have attracted considerable research attention due to their redox, electron-withdrawing and charge-carrier transport properties, as well as their excellent chemical, thermal, and photochemical stabilities. Naphthalene diimide (NDI) and perylene diimide (PDI) can be unequivocally recognized as the most studied imide based building blocks for the preparation of high-performance electron transporting optoelectronic materials. Within these wide-ranging studies, considerable effort has been undertaken to functionalize both the bay positions and the nitrogen atom constituting the imide group (N-positions) to bring solubility, tune the molecular (opto)electronic characteristics, and build extended π-conjugated architectures. Despite interesting fluorescent properties, the N-(alkyl)benzothioxanthene-3,4-dicarboximide (BTI), a sulfur containing rylene-imide dye, has not yet triggered such interest. Exclusively functionalized on the N-position for imaging and staining applications, we recently focused our attention in functionalizing the p-conjugated core of this forgotten dye for the preparation of new and original materials for organic electronics, but not only… 

Clément Cabanetos: clement.cabanetos@cnrs.fr

 After graduation in 2008, Clément Cabanetos undertook a PhD at the CEISAM laboratory (Nantes, France) on the synthesis of new crosslinkable polymers for nonlinear optical applications. Shortly after his thesis defense, he joined the group of Jean Fréchet (KAUST, (Saudi Arabia) as a postdoctoral fellow to prepare efficient π-conjugated macromolecular materials for organic photovoltaics. In 2013, he was recruited as a permanent CNRS researcher and joined the MOLTECH-Anjou laboratory in Angers to develop new and original concepts for organic electronics. He then defended his habilitation in 2018 (associate professorship) and received in 2019 the CNRS bronze medal that awards young and promising researchers. Recently (august 2021) he moved to Seoul in a joint French (CNRS)-Korean International laboratory (2BFUEL) hosted by the Yonsei University where he was promoted director in September 2022.

Alexina Ollier

Academic Affiliation: University of Basel

Research interest: 2D materials in device form(back gate +tunnel barrier+sample), Quantum effects in 2D materials or molecular structures, SPM technics mostly AFM, MFM, and STM.

Pavel Jelinek

Academic Affiliation: Institute of Physics of the Czech Academy of Sciences (FZU)

Expertise: SPM, DFT, molecular electronics, on-surface chemistry, molecular magnetism

Harald Brune

Academic Affiliation: Ecole Polytechnique Fédérale de Lausanne (EPFL)

Research Interests: Exploration of the novel physical and chemical properties arising when metals shrink to the nanoscale

Research stay period: Sept 13 ~ Dec 10, 2022

Vibhuti Narayan Rai

Academic Affiliation: Karlsruhe Institute of Technology

Current project: Mechanism Behind Single Molecules Electroluminescence by Timeresolved STM Measurements

Han-woong Yeom

Academic Affiliation: CALDES, IBS & POSTECH

Title: Nano-tsunami along atomic chains and domain walls for robust informatics

Abstract:

Storing and manipulating information in robust and dissipationless ways is of prime interest in various fields of science and technology. Using topologically protected local excitations, form examples, skyrmions and Majorana fermions, such robust informatics may be realized. This talk reviews our own approach to this issue, which deals with new types of solitons in electronic systems. We will first discuss atomic chains formed on silicon surfaces in charge-density-wave ground states and their solitons. We recently identified individual electronic solitons in indium atomic chains on a Si(111) surface and, more recently, in silicon chains on stepped silicon surfaces . Due to their unique structures, they represent unprecedented topological systems of Z₄ [1] and Z₃ [2], respectively, with three and two distinct solitons. These solitons can store, deliver, and operate multi-level information bits, which are protected topologically [3]. We further demonstrate solitons with higher multiplicity can be formed as a form of mobile kinks [4] along the charge-density-wave domain walls on a 2D material of 1T-TaS₂ [5]. Thus, the possibility of multi-level and topologically protected information processing with solitons, or solitonics, is well demonstrated. Further studies on soliton-defect, soliton-soliton, and soliton-excitation interactions are exciting for soliton applications.

References:

[1] S. M. Cheon, S. H. Lee, T. H. Kim, and H. W. Yeom, Science 350, 182 (2015).

[2] J. W. Park, E. Do, J. S. Shin, S. K. Song, O. P. Jelinek, and H. W. Yeom, Nature Nanotechnology 17, 244 (2022).

[3] S. M. Cheon, T. H. Kim, and H. W. Yeom, Nature Physics 13, 444 (2017).

[4] J. W. Lee, J. W. Park, and H. W. Yeom, PRL, under review (2022).

[5] D. Cho, G. Gye, J. Lee, S. H. Lee, L. Wnag, S-W. Cheong, and H. W. Yeom, Nature Commun. 8, 392 (2017)

Han Woong Yeom^1,2

¹Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science, Pohang 37673, Korea.

²Department of Physics, POSTECH, Pohang 37673, Korea.

Leonard Edens

Academic Affiliation: CIC nanoGUNE

Expertise: Materials, Thermoelectricity, Thin Films and Nanotechnology, Topological Insulators, Condensed Matter Physics

Wolf-Dieter Schneider

Academic Affiliation: Ecole Polytechnique Fédérale de Lausanne (EPFL)

Research Interests: Nanoscale Surface Physics, Solid State Physics, Nuclear Physics

Research stay period: Oct 23 ~ Nov 19, 2022

Ashley Jiwon Shin

Academic Affiliation: University of California, Los Angeles

Research area: Photophysical investigation of Yb (III) complexes and their potential application as quantum qubits or sensors and spectral characterization and analysis of semiconductor nanoplatelets

Research stay period: Oct 4 ~ Oct 15, 2022

Adam Kollin

Academic Affiliation: RHK Technology, Inc.

Click here to learn more about the visitor

Jingcheng Li

Academic Affiliation: Sun Yat-sen University

Title: Inducing magnetic properties in graphene nanostructures

Abstract:

Spin in carbon-based materials shows long coherence time, tunable coupling strength, and can be incorporated into scalable carbon platform, which makes it promising for quantum computing and spintronics applications.  Predictions state that graphene structures with specific edge topology can spontaneously develop magnetism, but the difficulty in their synthesis and magnetism characterization hinders the experimental verification. Here in this talk, I will show you our latest results on the observation and manipulation of magnetic moments in such graphene open-shell nanostructures. The graphene open-shell nanostructures with different edge topology, size and doping are created on a gold surface through on-surface synthesis route with atomic precision. Using scanning tunneling spectroscopy, we can detect the presence of electron spins and map their localization. With the experimental results and theoretical simulations, I will demonstrate that how the electronic correlations, πbond frustration or topological band engineering can be used to induce spin states in graphene nanostructures.

Youngchan Kim

Academic Affiliation: University of Surrey

Research Interests: Quantum Biology, Biophotonics, FRET, FCS, Anisotropy

Research stay period: Aug 16 ~ Aug 16, 2022

Yousoo Kim

Academic Affiliation: University of Tokyo

Research interests: Surface Science, Molecular Interface, Scanning Tunneling Microscopy

Jens Wiebe

Academic Affiliation: University of Hamburg

Research Interests: Scanning Probe Methods

Research stay period: July 23 ~ Aug 12, 2022

Arzhang Ardavan

Academic Affiliation: University of Oxford

Research Interests: Condensed matter physics

Research stay period: July 20 ~ July 21, 2022

Paul Weiss

Academic Affiliation: University of California, Los Angeles

Research Interests: Atomic-scale surface chemistry and physics, molecular devices, nanolithography, biophysics, and neuroscience.

Research stay period: July 7

Mario Ruben

Academic Affiliation: KIT Karlsruhe

Research Interests: Chemistry, Physics

Research stay period: June 28 ~ July 2, 2022

Daniel Loss

Academic Affiliation: University of Basel

Research Interests: Quantum Theory of Condensed Matter and Quantum Information Science

Research stay period: June 28 ~ July 2, 2022

Valeria Sheina

Academic Affiliation: University Paris-Saclay

Research field: Electrical detection of spin resonance, from Anomalous Hall effect to spin-polarized STM

Research stay period: June 28 ~ July 1, 2022

Franz Josef Giessibl

Academic Affiliation: University of Regensburg

Research Interests: Atomic Force Microscopy, Surface Science, Materials Science, Scanning Tunneling Microscopy, Quantum Physics

Research stay period: June 14 ~ June 18, 2022

William Koll

Academic Affiliation: Ohio State University

Research Area: Spintronics, Topological Phenomena, Condensed Matter Physics

Research stay period: June 2 ~ June 24, 2022

Ryo Kawaguchi

Academic Affiliation: Tohoku University

Research Area: Characterization of spin of single molecule magnet on thin superconducting substrate

Research stay period: March 15 ~ May 10 , 2022

Academic Affiliation: Tohoku University

Research Area: Scanning Probe Microscopy

Research stay period: March 16 ~ April 15 , 2022