Article
Multidisciplinary Sciences
Anuva Aishwarya, Arjun Raghavan, Sean Howard, Zhuozhen Cai, Gohil S. Thakur, Choongjae Won, Sang-Wook Cheong, Claudia Felser, Vidya Madhavan
Summary: Spin chains in solid state materials are important quantum systems with potential applications. This study used low-temperature scanning tunneling microscopy to reveal long-lifetime excitations in a specific material, providing new insights for increasing spin lifetimes and quantum applications.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Chemistry, Multidisciplinary
Chao Li, Jan Homberg, Alexander Weismann, Richard Berndt
Summary: The study reveals that AlPc molecules lose their spin moment on superconducting Pb(100) but molecular magnetism can be restored by surrounding molecules. Unlike other molecules, AlPc molecules have similar magnetic moments and lead to unusually high conductance peaks.
Article
Chemistry, Multidisciplinary
Christian Waeckerlin, Ales Cahlik, Joseba Goikoetxea, Oleksandr Stetsovych, Dania Medvedeva, Jesus Redondo, Martin Svec, Bernard Delley, Martin Ondracek, Andres Pinar, Maria Blanco-Rey, Jindrich Kolorenc, Andres Arnau, Pavel Jelinek
Summary: One-dimensional metal-organic coordination polymers possess complex magnetic structures that can be tuned by altering their chemical composition. However, the detailed understanding of the interactions governing electronic and magnetic properties in low-dimensional systems is still incomplete.
Article
Chemistry, Multidisciplinary
Katerina Vaxevani, Jingcheng Li, Stefano Trivini, Jon Ortuzar, Danilo Longo, Dongfei Wang, Jose Ignacio Pascual
Summary: The study shows that a proximity-induced superconducting gold film can sustain spin excitations of a FeTPP-Cl molecule for over 80 ns, which decreases with increasing film thickness. This suggests potential new routes for manipulating the spin lifetime of quantum spins on surfaces using proximitized gold electrodes.
Article
Chemistry, Multidisciplinary
Katerina Vaxevani, Jingcheng Li, Stefano Trivini, Jon Ortuzar, Danilo Longo, Dongfei Wang, Jose Ignacio Pascual
Summary: This study demonstrates that the use of proximitized superconducting gold film can prolong the spin excitation lifetime of FeTPP-Cl molecule to more than 80 ns. The research findings suggest that increasing film thickness and decreasing superconducting gap will reduce the spin lifetime.
Article
Chemistry, Multidisciplinary
Alexander Mehler, Nicolas Neel, Elena Voloshina, Yuriy Dedkov, Jorg Kroger
Summary: The study demonstrates the growth of graphene on h-BN through thermal decomposition and catalytic assistance of metal substrates, as well as the epitaxial growth of h-BN on Pt(111). Different honeycomb structures of graphene on h-BN and the observation of distinct superstructures at small probe-surface distances are highlighted in this study.
Article
Chemistry, Multidisciplinary
Haowen Zhou, William E. Perreault, Nandini Mukherjee, Richard N. Zare
Summary: The collision dynamics between a pair of aligned molecules in the presence of a partial-wave resonance provide a sensitive probe of long-range anisotropic forces. By controlling the collision temperature and geometry, the cold rotationally inelastic scattering of optically state-prepared D-2 molecules was studied.
Article
Physics, Condensed Matter
Zhe Li, Fernando Delgado, Mei Du, Chen He, Koen Schouteden, Chris Van Haesendonck, Ewald Janssens, Andres Arnau, Peter Lievens, Jorge Cerda
Summary: Using scanning tunneling microscopy and inelastic electron tunneling spectroscopy, researchers have observed different spin excitation energies for individual Co and Cr dopants in ultrathin NaCl films. The spin excitation energy for Co dopants is relatively high at around 36 meV, while the spin excitation energy for Cr dopants is much lower at around 2.5 meV. Electronic multiplet calculations and first-principles calculations confirm the spin excitation induced IETS and quantitatively reveal the magnetic anisotropies for both Co and Cr.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2022)
Article
Chemistry, Multidisciplinary
Xiangzhi Meng, Jenny Moeller, Masoud Mansouri, Daniel Sanchez-Portal, Aran Garcia-Lekue, Alexander Weismann, Chao Li, Rainer Herges, Richard Berndt
Summary: Spin-flip excitations of iron porphyrin molecules on Au(111) were investigated using a low-temperature scanning tunneling microscope. The molecules exhibited two distinct adsorption configurations on the surface, with different magnetic anisotropy energies. Density functional theory calculations showed that the different structures and excitation energies were a result of different occupations of the Fe 3d levels. We demonstrated that the magnetic anisotropy energy could be controlled by changing the adsorption site, orientation, or tip-molecule distance.
Article
Chemistry, Multidisciplinary
Yi-Ying Sung, Harmina Vejayan, Christopher J. Baddeley, Neville V. Richardson, Federico Grillo, Renald Schaub
Summary: On-surface synthesis with designer precursor molecules is an effective method for preparing graphene nanoribbons (GNRs) with tunable electronic properties. The band gap of GNRs doped with heteroatoms remains unchanged, but hydrogenation can engineer a tunable band gap. Surface-confined hydrogenation studies on 7-armchair GNRs grown on Au(111) surfaces reveal a self-limited hydrogenation process. The electronic properties of the GNR/Au(111) system can be modified by edge and basal-plane hydrogenation, and a mechanism for the hydrogenation process is proposed.
Article
Chemistry, Multidisciplinary
Nguyen Huu Lam, Phuong Lien Nguyen, Byoung Ki Choi, Trinh Thi Ly, Ganbat Duvjir, Tae Gyu Rhee, Yong Jin Jo, Tae Heon Kim, Chris Jozwiak, Aaron Bostwick, Eli Rotenberg, Younghun Hwang, Young Jun Chang, Jaekwang Lee, Jungdae Kim
Summary: In this study, the strength of spin-orbit coupling in NiTe2 is shown to be tunable through Se substitution, resulting in shifts of the bulk Dirac point while maintaining the type-II Dirac band. This approach provides an effective means of controlling the type-II Dirac band in NiTe2 and can be applicable to other topological materials.
Article
Multidisciplinary Sciences
Alexander Kerelsky, Carmen Rubio-Verdu, Lede Xian, Dante M. Kennes, Dorri Halbertal, Nathan Finney, Larry Song, Simon Turkel, Lei Wang, Kenji Watanabe, Takashi Taniguchi, James Hone, Cory Dean, Dmitri N. Basov, Angel Rubio, Abhay N. Pasupathy
Summary: This study demonstrates the formation of emergent correlated phases in multilayer rhombohedral graphene without the need for twisted van der Waals layers. The study shows that two layers of bilayer graphene twisted by a tiny angle can host large regions of uniform rhombohedral four-layer graphene with a sharp van Hove singularity. Furthermore, the study suggests that the broken symmetry state in ABCA graphene could be attributed to a charge-transfer excitonic insulator or a ferrimagnet.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Chemistry, Physical
V. Carnevali, A. Sala, P. Biasin, M. Panighel, G. Comelli, M. Peressi, C. Africh
Summary: The electronic properties of graphene can be modified by local interaction with a metal substrate. This article proposes a reliable method of evaluating the interaction between graphene and substrate by testing the tunneling current. This method expands the capabilities of standard STM systems for studying graphene/substrate complexes.
Review
Chemistry, Multidisciplinary
Wenbing Peng, Haolin Wang, Hui Lu, Lei Yin, Yue Wang, Bruno Grandidier, Deren Yang, Xiaodong Pi
Summary: Understanding the band alignment, interface states, interface coupling, and carrier transport properties of semiconductor heterojunctions (SHs) is crucial for designing and fabricating semiconductor structures and devices. STM and STS have played significant roles in studying the properties of SHs, such as spatial structures and electronic band structures, to propose mechanisms for carrier transport.
Article
Chemistry, Multidisciplinary
Anna Kuzmina, Markus Parzefall, Patrick Back, Takashi Taniguchi, Kenji Watanabe, Achint Jain, Lukas Novotny
Summary: By controlled stacking of graphene layers, the limitation of single-layer graphene as a material for light-emitting devices has been overcome, enabling twist-controlled resonant light emission. Experimental findings show light emission irrespective of the crystallographic alignment between the graphene electrodes, with a spectrally tunable resonant peak in the near-infrared range.
Article
Multidisciplinary Sciences
Samuel Stolz, Oliver Groening, Jan Prinz, Harald Brune, Roland Widmer
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2020)
Article
Instruments & Instrumentation
Werner M. J. van Weerdenburg, Manuel Steinbrecher, Niels P. E. van Mullekom, Jan W. Gerritsen, Henning von Allworden, Fabian D. Natterer, Alexander A. Khajetoorians
Summary: Researchers have successfully demonstrated the operation of ESR and pump-probe spectroscopy in an ultra-high vacuum STM at mK temperatures, enabling the detection of spin dynamics at the atomic scale. By implementing GHz compatible cabling, they achieved significant RF amplitudes for ESR measurements on individual molecules, and measured the spin relaxation time T-1 of individual Fe atoms.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2021)
Article
Chemistry, Multidisciplinary
Samuel Stolz, Michael Bauer, Carlo A. Pignedoli, Nils Krane, Max Bommert, Elia Turco, Nicolo Bassi, Amogh Kinikar, Nestor Merino-Diez, Roland Hany, Harald Brune, Oliver Groning, Roland Widmer
Summary: This study investigates the impact of chirality transfer and ensemble effect on thermally activated azide-alkyne Huisgen cycloaddition on well-defined and chiral intermetallic PdGa{111} surfaces. Dominating ensemble effect and chirality transfer from the substrate to reaction products are observed, revealing the potential of PdGa as an asymmetric heterogeneous catalyst. Mechanistic insight into enantioselective reactions at chiral surfaces is challenging but crucial for understanding catalytic activity differences observed on Pd-1- and Pd-3-terminated PdGa{111} surfaces.
COMMUNICATIONS CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Aparajita Singha, Daria Sostina, Christoph Wolf, Safa L. Ahmed, Denis Krylov, Luciano Colazzo, Pierluigi Gargiani, Stefano Agrestini, Woo-Suk Noh, Jae-Hoon Park, Marina Pivetta, Stefano Rusponi, Harald Brune, Andreas J. Heinrich, Alessandro Barla, Fabio Donati
Summary: This study successfully resolves the magnetism of individual orbitals in Gd and Ho single atoms by combining X-ray magnetic circular dichroism, multiplet calculations, and density functional theory. Contrary to previous assumptions, a charge transfer mechanism leading to an unconventional singly ionized configuration was identified. This work highlights the role of valence electrons in determining the quantum level structure and spin-dependent transport properties of lanthanide-based nanomagnets.
Article
Multidisciplinary Sciences
A. Singha, P. Willke, T. Bilgeri, X. Zhang, H. Brune, F. Donati, A. J. Heinrich, T. Choi
Summary: Atomic scale engineering of magnetic fields is crucial for miniaturizing quantum devices and precise control of quantum systems. Surface-supported single atom magnets with a giant magnetic anisotropy energy exhibit long-term stability of spin states at low temperatures. Dy adsorbed onto MgO shows a high MAE and a life time of several days at low temperatures, making it a promising candidate for magnetic nanostructures.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Samuel Stolz, Martina Danese, Marco Di Giovannantonio, Jose Urgel, Qiang Sun, Amogh Kinikar, Max Bommert, Shantanu Mishra, Harald Brune, Oliver Groning, Daniele Passerone, Roland Widmer
Summary: This study investigates the dehalogenation of prochiral 5-bromo-7-methylbenz(a)anthracene (BMA) on prototypical, chiral, intermetallic PdGa{111} surfaces under ultrahigh vacuum conditions, demonstrating asymmetric halogen elimination and a significant dependence on the atomic termination of the PdGa{111} surfaces for the dehalogenation temperature of the BMA surface enantiomers.
ADVANCED MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Fabio Donati, Marina Pivetta, Christoph Wolf, Aparajita Singha, Christian Waeckerlin, Romana Baltic, Edgar Fernandes, Jean-Guillaume De Groot, Safa Lamia Ahmed, Luca Persichetti, Corneliu Nistor, Jan Dreiser, Alessandro Barla, Pietro Gambardella, Harald Brune, Stefano Rusponi
Summary: By using X-ray absorption spectroscopy, the electronic configuration of dysprosium atoms on MgO(100) thin films can be adjusted by changing the MgO thickness from 2.5 to 9 monolayers, resulting in different magnetic stabilities. Hysteresis loops indicate long magnetic lifetimes for both configurations.
Article
Chemistry, Multidisciplinary
Sergio Vlaic, Dimitris Mousadakos, Safia Ouazi, Stefano Rusponi, Harald Brune
Summary: In this study, the magnetic properties and atomic morphology of bimetallic two-dimensional nanoislands grown on metal surfaces were investigated. The blocking temperature was found to be greatly increased by modifying the interfaces and capping the islands with different materials.
Article
Chemistry, Multidisciplinary
Ales Cahlik, Danyang Liu, Berk Zengin, Mert Taskin, Johannes Schwenk, Fabian Donat Natterer
Summary: The on-surface synthesis of nano-graphenes has opened up possibilities for structures beyond silicon-based technology. Researchers have been investigating the magnetic properties of graphene-nanoribbons (GNRs) for spintronic applications. A new method using a binary alloy Cu3Au(111) has been developed, allowing for gold-like synthesis of nano-graphenes compatible with spin polarization and electronic decoupling known from copper. This versatile platform will be a valuable tool for advanced study of magnetic nano-graphenes.
NANOSCALE ADVANCES
(2023)
Article
Multidisciplinary Sciences
Danyang Liu, Jens Oppliger, Ales Cahlik, Catherine Witteveen, Fabian O. von Rohr, Fabian Donat Natterer
Summary: We present a simple method for integrating a magnetic field into a low-temperature scanning tunneling microscope (STM) by attaching an NdFeB permanent magnet to a magnetizable sample plate. To ensure compatibility with high-temperature sample cleaning procedures, we incorporate the irreversible demagnetization of the magnet into our preparation cycle. By sacrificing the magnet and attaching a new one in-situ, we can predict the magnitude and orientation of magnetic flux at any location with respect to the magnet and sample plate. Our concept is a feasible solution for field-dependent surface science studies that require fields up to 400 mT and involve detrimental heating procedures. Accessible magnetic field generation. Selectable field strength and orientation. Compatible with high-temperature sample preparation.
Article
Multidisciplinary Sciences
Jens Oppliger, Berk Zengin, Danyang Liu, Kevin Hauser, Catherine Witteveen, Fabian von Rohr, Fabian Donat Natterer
Summary: Researchers propose an adaptive sparse sampling (ASS) approach for quasiparticle interference imaging, which gradually accumulates sparsely sampled local density of states (LDOS) measurements using compressive sensing recovery. The method can be combined with regular topographic images to improve the imaging quality.
Article
Physics, Multidisciplinary
Berk Zengin, Jens Oppliger, Danyang Liu, Lorena Niggli, Tohru Kurosawa, Fabian D. Natterer
Summary: The discovery of quantum materials requires extensive spectroscopic studies against multiple degrees of freedom, which can be slow using traditional methods. By combining sparse sampling and parallel spectroscopy, measurements can be significantly accelerated, potentially advancing the discovery of quantum materials.
PHYSICAL REVIEW RESEARCH
(2021)
Article
Physics, Multidisciplinary
Anastasiia Skurativska, Stepan S. Tsirkin, Fabian D. Natterer, Titus Neupert, Mark H. Fischer
Summary: This study proposes a method to impose a tailored potential onto a single graphene layer through local perturbations, resulting in flat energy bands. The research demonstrates the topological nature of these bands and the manifestation of nontrivial topology in corner-localized states.
PHYSICAL REVIEW RESEARCH
(2021)
Article
Materials Science, Multidisciplinary
Manuel Steinbrecher, Werner M. J. van Weerdenburg, Etienne F. Walraven, Niels P. E. van Mullekom, Jan W. Gerritsen, Fabian D. Natterer, Danis Badrtdinov, Alexander N. Rudenko, Vladimir V. Mazurenko, Mikhail Katsnelson, Ad van der Avoird, Gerrit C. Groenenboom, Alexander A. Khajetoorians
Summary: The research successfully determined the fine structure and geometry of an individual titanium-hydride molecule using a newly developed ESR scanning tunneling microscope in combination with ab initio methods, demonstrating a significant anisotropy of the g tensor. The findings provide insight into the structure and dynamics of individual molecules.
Article
Physics, Multidisciplinary
Jens Oppliger, Fabian Donat Natterer
PHYSICAL REVIEW RESEARCH
(2020)
