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Esat T, Borodin D, Oh J, Heinrich AJ, Tautz FS, Bae Y, Temirov R. A quantum sensor for atomic-scale electric and magnetic fields. NATURE NANOTECHNOLOGY 2024:10.1038/s41565-024-01724-z. [PMID: 39054385 DOI: 10.1038/s41565-024-01724-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2024] [Accepted: 06/18/2024] [Indexed: 07/27/2024]
Abstract
The detection of faint magnetic fields from single-electron and nuclear spins at the atomic scale is a long-standing challenge in physics. While current mobile quantum sensors achieve single-electron spin sensitivity, atomic spatial resolution remains elusive for existing techniques. Here we fabricate a single-molecule quantum sensor at the apex of the metallic tip of a scanning tunnelling microscope by attaching Fe atoms and a PTCDA (3,4,9,10-perylenetetracarboxylic-dianhydride) molecule to the tip apex. We address the molecular spin by electron spin resonance and achieve ~100 neV resolution in energy. In a proof-of-principle experiment, we measure the magnetic and electric dipole fields emanating from a single Fe atom and an Ag dimer on an Ag(111) surface with sub-angstrom spatial resolution. Our method enables atomic-scale quantum sensing experiments of electric and magnetic fields on conducting surfaces and may find applications in the sensing of spin-labelled biomolecules and of spin textures in quantum materials.
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Affiliation(s)
- Taner Esat
- Peter Grünberg Institute (PGI-3), Forschungszentrum Jülich, Jülich, Germany.
- Jülich Aachen Research Alliance (JARA), Fundamentals of Future Information Technology, Jülich, Germany.
| | - Dmitriy Borodin
- Center for Quantum Nanoscience (QNS), Institute for Basic Science (IBS), Seoul, South Korea
- Department of Physics, Ewha Womans University, Seoul, South Korea
| | - Jeongmin Oh
- Center for Quantum Nanoscience (QNS), Institute for Basic Science (IBS), Seoul, South Korea
- Department of Physics, Ewha Womans University, Seoul, South Korea
| | - Andreas J Heinrich
- Center for Quantum Nanoscience (QNS), Institute for Basic Science (IBS), Seoul, South Korea.
- Department of Physics, Ewha Womans University, Seoul, South Korea.
| | - F Stefan Tautz
- Peter Grünberg Institute (PGI-3), Forschungszentrum Jülich, Jülich, Germany
- Jülich Aachen Research Alliance (JARA), Fundamentals of Future Information Technology, Jülich, Germany
- Experimentalphysik IV A, RWTH Aachen University, Aachen, Germany
| | - Yujeong Bae
- Center for Quantum Nanoscience (QNS), Institute for Basic Science (IBS), Seoul, South Korea.
- Department of Physics, Ewha Womans University, Seoul, South Korea.
- Empa, Swiss Federal Laboratories for Materials Science and Technology, nanotech@surfaces Laboratory, Dübendorf, Switzerland.
| | - Ruslan Temirov
- Peter Grünberg Institute (PGI-3), Forschungszentrum Jülich, Jülich, Germany
- Jülich Aachen Research Alliance (JARA), Fundamentals of Future Information Technology, Jülich, Germany
- Faculty of Mathematics and Natural Sciences, Institute of Physics II, University of Cologne, Cologne, Germany
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2
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de Campos Ferreira R, Sagwal A, Doležal J, Canola S, Merino P, Neuman T, Švec M. Resonant Tip-Enhanced Raman Spectroscopy of a Single-Molecule Kondo System. ACS NANO 2024; 18:13164-13170. [PMID: 38711331 PMCID: PMC11112976 DOI: 10.1021/acsnano.4c02105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 04/11/2024] [Accepted: 04/24/2024] [Indexed: 05/08/2024]
Abstract
Tip-enhanced Raman spectroscopy (TERS) under ultrahigh vacuum and cryogenic conditions enables exploration of the relations between the adsorption geometry, electronic state, and vibrational fingerprints of individual molecules. TERS capability of reflecting spin states in open-shell molecular configurations is yet unexplored. Here, we use the tip of a scanning probe microscope to lift a perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) molecule from a metal surface to bring it into an open-shell spin one-half anionic state. We reveal a correlation between the appearance of a Kondo resonance in differential conductance spectroscopy and concurrent characteristic changes captured by the TERS measurements. Through a detailed investigation of various adsorbed and tip-contacted PTCDA scenarios, we infer that the Raman scattering on suspended PTCDA is resonant with a higher excited state. Theoretical simulation of the vibrational spectra enables a precise assignment of the individual TERS peaks to high-symmetry Ag modes, including the fingerprints of the observed spin state. These findings highlight the potential of TERS in capturing complex interactions between charge, spin, and photophysical properties in nanoscale molecular systems and suggest a pathway for designing single-molecule spin-optical devices.
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Affiliation(s)
| | - Amandeep Sagwal
- Institute
of Physics, Czech Academy of Sciences; Cukrovarnická 10/112, Praha 6 CZ16200, Czech Republic
- Faculty
of Mathematics and Physics, Charles University; Ke Karlovu 3, Praha 2 CZ12116. Czech Republic
| | - Jiří Doležal
- Institute
of Physics, Czech Academy of Sciences; Cukrovarnická 10/112, Praha 6 CZ16200, Czech Republic
- Institute
of Physics, École Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland
| | - Sofia Canola
- Institute
of Physics, Czech Academy of Sciences; Cukrovarnická 10/112, Praha 6 CZ16200, Czech Republic
| | - Pablo Merino
- Instituto
de Ciencia de Materiales de Madrid; CSIC, Sor Juana Inés de la Cruz 3, Madrid E28049, Spain
| | - Tomáš Neuman
- Institute
of Physics, Czech Academy of Sciences; Cukrovarnická 10/112, Praha 6 CZ16200, Czech Republic
| | - Martin Švec
- Institute
of Physics, Czech Academy of Sciences; Cukrovarnická 10/112, Praha 6 CZ16200, Czech Republic
- Institute
of Organic Chemistry and Biochemistry, Czech
Academy of Sciences; Flemingovo náměstí 542/2. Praha 6 CZ16000, Czech Republic
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3
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Kaur R, Kaur S, Randhawa DKK, Sharma R, Kaur P. Mechanism of rectification and negative differential resistance in single-molecule junctions with asymmetric anchoring groups: a DFT study. J Mol Model 2023; 29:340. [PMID: 37840050 DOI: 10.1007/s00894-023-05747-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 10/03/2023] [Indexed: 10/17/2023]
Abstract
CONTEXT This study aims to investigate the electronic transport properties of tetracene molecule connected to gold (Au) electrodes with asymmetric anchoring groups. More specifically, we investigate the effect of asymmetric electrode coupling on the rectification ratio of tetracene-based molecular device. To introduce coupling asymmetry in these junctions, one end of the tetracene molecule is terminated with thiol (-SH) or isocyanide (-NC) while the other end with amine (-NH2) or nitro (-NO2) anchoring group. The results indicate that the electronic transport behavior is affected by the nature of molecule-electrode coupling, and the rectification ratio can be modulated by a proper choice of the anchoring groups. We reveal that the tetracene molecule when connected with isocyanide and amine combination exhibits remarkable rectifying performance (with a rectification ratio of 74) in contrast with other configurations. Furthermore, a prominent negative differential resistance (NDR) feature is observed when the molecule is connected with thiol as one of the anchors. Our present findings with excellent rectifying performance and negative differential resistance pave a new roadmap for designing multifunctional molecular devices. METHODS By applying non-equilibrium Green's function (NEGF) formalism combined with density functional theory (DFT) Atomistic Tool Kit software package, the electronic transport properties of tetracene molecule connected to gold electrodes with asymmetric anchoring groups have been investigated. The calculations were performed using the Perdew-Burke-Ernzerhof (PBE) parameterization of DFT within generalized gradient approximation (GGA) exchange-correlation functional. To improve calculation precision and save computational efforts, the molecule and anchor groups were double-ζ (DZ) polarized, while single-ζ (SZ) polarized basis set was used for gold electrodes.
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Affiliation(s)
- Rupendeep Kaur
- Department of Electronics Technology, Guru Nanak Dev University, Amritsar, 143005, India
| | - Sukhdeep Kaur
- Department of Electronics Technology, Guru Nanak Dev University, Amritsar, 143005, India.
| | - Deep Kamal Kaur Randhawa
- Department of Engineering and Technology, Guru Nanak Dev University Regional Campus, Jalandhar, 144007, India
| | - Rahul Sharma
- Department of Electronics and Communication Engineering, Lovely Professional University, Phagwara, 144411, India
| | - Pawandeep Kaur
- Department of Electronics Technology, Guru Nanak Dev University, Amritsar, 143005, India
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Scheidt J, Diener A, Maiworm M, Müller KR, Findeisen R, Driessens K, Tautz FS, Wagner C. Concept for the Real-Time Monitoring of Molecular Configurations during Manipulation with a Scanning Probe Microscope. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2023; 127:13817-13836. [PMID: 37492192 PMCID: PMC10364088 DOI: 10.1021/acs.jpcc.3c02072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 06/20/2023] [Indexed: 07/27/2023]
Abstract
A bold vision in nanofabrication is the assembly of functional molecular structures using a scanning probe microscope (SPM). This approach requires continuous monitoring of the molecular configuration during manipulation. Until now, this has been impossible because the SPM tip cannot simultaneously act as an actuator and an imaging probe. Here, we implement configuration monitoring using experimental data other than images collected during the manipulation process. We model the manipulation as a partially observable Markov decision process (POMDP) and approximate the actual configuration in real time using a particle filter. To achieve this, the models underlying the POMDP are precomputed and organized in the form of a finite-state automaton, allowing the use of complex atomistic simulations. We exemplify the configuration monitoring process and reveal structural motifs behind measured force gradients. The proposed methodology marks an important step toward the piece-by-piece creation of supramolecular structures in a robotic and possibly automated manner.
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Affiliation(s)
- Joshua Scheidt
- Peter
Grünberg Institut (PGI-3), Forschungszentrum
Jülich, 52425 Jülich, Germany
- Jülich
Aachen Research Alliance (JARA)-Fundamentals of Future Information
Technology, 52425 Jülich, Germany
- Data
Science and Knowledge Engineering, Maastricht
University, 6229 EN Maastricht, The Netherlands
| | - Alexander Diener
- Peter
Grünberg Institut (PGI-3), Forschungszentrum
Jülich, 52425 Jülich, Germany
- Jülich
Aachen Research Alliance (JARA)-Fundamentals of Future Information
Technology, 52425 Jülich, Germany
- Data
Science and Knowledge Engineering, Maastricht
University, 6229 EN Maastricht, The Netherlands
| | - Michael Maiworm
- Laboratory
for Systems Theory and Automatic Control, Otto-von-Guericke-Universität Magdeburg, 39106 Magdeburg, Germany
| | - Klaus-Robert Müller
- Max
Planck Institute for Informatics, 66123 Saarbrücken, Germany
- Machine Learning
Group, Technische Universität Berlin, 10587 Berlin, Germany
- Department
of Artificial Intelligence, Korea University, Seoul 136-713, South Korea
| | - Rolf Findeisen
- Control
and Cyber-Physical Systems Laboratory, Technische
Universität Darmstadt, 64289 Darmstadt, Germany
| | - Kurt Driessens
- Data
Science and Knowledge Engineering, Maastricht
University, 6229 EN Maastricht, The Netherlands
| | - F. Stefan Tautz
- Peter
Grünberg Institut (PGI-3), Forschungszentrum
Jülich, 52425 Jülich, Germany
- Jülich
Aachen Research Alliance (JARA)-Fundamentals of Future Information
Technology, 52425 Jülich, Germany
- Department
of Artificial Intelligence, Korea University, Seoul 136-713, South Korea
| | - Christian Wagner
- Peter
Grünberg Institut (PGI-3), Forschungszentrum
Jülich, 52425 Jülich, Germany
- Jülich
Aachen Research Alliance (JARA)-Fundamentals of Future Information
Technology, 52425 Jülich, Germany
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5
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Maier S, Stöhr M. Molecular assemblies on surfaces: towards physical and electronic decoupling of organic molecules. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2021; 12:950-956. [PMID: 34540518 PMCID: PMC8404214 DOI: 10.3762/bjnano.12.71] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 08/04/2021] [Indexed: 06/13/2023]
Affiliation(s)
- Sabine Maier
- Department of Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erwin-Rommel-Str. 1, 91058 Erlangen, Germany
| | - Meike Stöhr
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, Netherlands
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6
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Žonda M, Stetsovych O, Korytár R, Ternes M, Temirov R, Raccanelli A, Tautz FS, Jelínek P, Novotný T, Švec M. Resolving Ambiguity of the Kondo Temperature Determination in Mechanically Tunable Single-Molecule Kondo Systems. J Phys Chem Lett 2021; 12:6320-6325. [PMID: 34228474 DOI: 10.1021/acs.jpclett.1c01544] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Determination of the molecular Kondo temperature (TK) poses a challenge in most cases when the experimental temperature cannot be tuned to a sufficient extent. We show how this ambiguity can be resolved if additional control parameters are present, such as magnetic field and mechanical gating. We record the evolution of the differential conductance by lifting an individual molecule from the metal surface with the tip of a scanning tunneling microscope. By fitting the measured conductance spectra with the single impurity Anderson model we are able to demonstrate that the lifting tunes the junction continuously from the strongly correlated Kondo-singlet to the free spin-1/2 ground state. In the crossover regime, where TK is similar to the temperature of experiment, the fitting yields ambiguous estimates of TK varying by an order of magnitude. We show that analysis of the conductance measured in two distinct external magnetic fields can be used to resolve this problem.
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Affiliation(s)
- Martin Žonda
- Department of Condensed Matter Physics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, CZ-121 16 Praha 2, Czech Republic
- Institute of Physics, Albert Ludwig University of Freiburg, Hermann-Herder-Strasse 3, 79104 Freiburg, Germany
| | - Oleksandr Stetsovych
- Institute of Physics, Czech Academy of Sciences, Cukrovarnická 10, CZ-162 00 Praha 6, Czech Republic
| | - Richard Korytár
- Department of Condensed Matter Physics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, CZ-121 16 Praha 2, Czech Republic
| | - Markus Ternes
- Institute of Physics II B, RWTH Aachen University, 52074 Aachen, Germany
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, Jülich Germany
| | - Ruslan Temirov
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, Jülich Germany
- Faculty of Mathematics and Natural Sciences, Institute of Physics II, University of Cologne, 50937 Cologne, Germany
| | - Andrea Raccanelli
- Peter Grünberg Institut (Cryo-Lab), Forschungszentrum Jülich, JülichGermany
| | - F Stefan Tautz
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, Jülich Germany
- Fundamentals of Future Information Technology, Jülich Aachen Research Alliance (JARA), Jülich, Germany
- Institute of Physics IV A, RWTH Aachen University, Aachen, Germany
| | - Pavel Jelínek
- Institute of Physics, Czech Academy of Sciences, Cukrovarnická 10, CZ-162 00 Praha 6, Czech Republic
- RCPTM, Palacky University, Šlechtitelu 27, 783 71 Olomouc, Czech Republic
| | - Tomáš Novotný
- Department of Condensed Matter Physics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, CZ-121 16 Praha 2, Czech Republic
| | - Martin Švec
- Institute of Physics, Czech Academy of Sciences, Cukrovarnická 10, CZ-162 00 Praha 6, Czech Republic
- RCPTM, Palacky University, Šlechtitelu 27, 783 71 Olomouc, Czech Republic
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7
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Bahlke MP, Schneeberger M, Herrmann C. Local decomposition of hybridization functions: Chemical insight into correlated molecular adsorbates. J Chem Phys 2021; 154:144108. [PMID: 33858153 DOI: 10.1063/5.0045640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Hybridization functions are an established tool for investigating the coupling between a correlated subsystem (often a single transition metal atom) and its uncorrelated environment (the substrate and any ligands present). The hybridization function can provide valuable insight into why and how strong correlation features such as the Kondo effect can be chemically controlled in certain molecular adsorbates. To deepen this insight, we introduce a local decomposition of the hybridization function, based on a truncated cluster approach, enabling us to study individual effects on this function coming from specific parts of the systems (e.g., the surface, ligands, or parts of larger ligands). It is shown that a truncated-cluster approach can reproduce the Co 3d and Mn 3d hybridization functions from periodic boundary conditions in Co(CO)4/Cu(001) and MnPc/Ag(001) qualitatively well. By locally decomposing the hybridization functions, it is demonstrated at which energies the transition metal atoms are mainly hybridized with the substrate or with the ligand. For the Kondo-active 3dx2-y2 orbital in Co(CO)4/Cu(001), the hybridization function at the Fermi energy is substrate-dominated, so we can assign its enhancement compared with ligand-free Co to an indirect effect of ligand-substrate interactions. In MnPc/Ag(001), the same is true for the Kondo-active orbital, but for two other orbitals, there are both direct and indirect effects of the ligand, together resulting in such strong screening that their potential Kondo activity is suppressed. A local decomposition of hybridization functions could also be useful in other areas, such as analyzing the electrode self-energies in molecular junctions.
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Affiliation(s)
- Marc Philipp Bahlke
- Department of Chemistry, University of Hamburg, Harbor Bldg. 610, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Michaela Schneeberger
- Department of Chemistry, University of Hamburg, Harbor Bldg. 610, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Carmen Herrmann
- Department of Chemistry, University of Hamburg, Harbor Bldg. 610, Luruper Chaussee 149, 22761 Hamburg, Germany
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8
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Friedrich N, Brandimarte P, Li J, Saito S, Yamaguchi S, Pozo I, Peña D, Frederiksen T, Garcia-Lekue A, Sánchez-Portal D, Pascual JI. Magnetism of Topological Boundary States Induced by Boron Substitution in Graphene Nanoribbons. PHYSICAL REVIEW LETTERS 2020; 125:146801. [PMID: 33064521 DOI: 10.1103/physrevlett.125.146801] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 08/10/2020] [Indexed: 06/11/2023]
Abstract
Graphene nanoribbons (GNRs), low-dimensional platforms for carbon-based electronics, show the promising perspective to also incorporate spin polarization in their conjugated electron system. However, magnetism in GNRs is generally associated with localized states around zigzag edges, difficult to fabricate and with high reactivity. Here we demonstrate that magnetism can also be induced away from physical GNR zigzag edges through atomically precise engineering topological defects in its interior. A pair of substitutional boron atoms inserted in the carbon backbone breaks the conjugation of their topological bands and builds two spin-polarized boundary states around them. The spin state was detected in electrical transport measurements through boron-substituted GNRs suspended between the tip and the sample of a scanning tunneling microscope. First-principle simulations find that boron pairs induce a spin 1, which is modified by tuning the spacing between pairs. Our results demonstrate a route to embed spin chains in GNRs, turning them into basic elements of spintronic devices.
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Affiliation(s)
| | - Pedro Brandimarte
- Donostia International Physics Center (DIPC), 20018 Donostia-San Sebastián, Spain
| | - Jingcheng Li
- CIC nanoGUNE BRTA, 20018 Donostia-San Sebastián, Spain
| | - Shohei Saito
- Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | | | - Iago Pozo
- Centro de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and Departamento de Química Orgánica, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Diego Peña
- Centro de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and Departamento de Química Orgánica, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Thomas Frederiksen
- Donostia International Physics Center (DIPC), 20018 Donostia-San Sebastián, Spain
- Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain
| | - Aran Garcia-Lekue
- Donostia International Physics Center (DIPC), 20018 Donostia-San Sebastián, Spain
- Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain
| | - Daniel Sánchez-Portal
- Donostia International Physics Center (DIPC), 20018 Donostia-San Sebastián, Spain
- Centro de Física de Materiales CSIC-UPV/EHU, 20018 Donostia-San Sebastián, Spain
| | - José Ignacio Pascual
- CIC nanoGUNE BRTA, 20018 Donostia-San Sebastián, Spain
- Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain
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9
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Soe WH, Manzano C, Robles R, Lorente N, Joachim C. On-Surface Atom-by-Atom-Assembled Aluminum Binuclear Tetrabenzophenazine Organometallic Magnetic Complex. NANO LETTERS 2020; 20:384-388. [PMID: 31846337 DOI: 10.1021/acs.nanolett.9b04040] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The Kondo effect results from the interactions of the conduction electrons in a metal bulk with localized magnetic impurities. While adsorbed atop a metallic surface, the on-surface nanoscale version of this effect is observed when a single magnetic atom or a single magnetic molecule (SMM) is interacting with the conduction electrons. SMMs are commonly organometallic complexes incorporating transition-metal atoms in different oxidation states. We demonstrate how a single nonmagnetic neutral tetrabenzo[a,c,j,h]phenazine molecule can be on-surface-coordinated with exactly two aluminum metal atoms (between Al(I) and Al(II) oxidation state on the Au(111) surface) by low-temperature scanning tunneling microscope (LT-STM) single-atom manipulation. It results in a Kondo measurable localized molecular magnetic moment. This opens a new way to design SMM complexes without the need for heavy transition-metal atoms and complex ligands to stabilize the molecular coordination sphere.
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Affiliation(s)
- We-Hyo Soe
- Centre d'Elaboration de Matériaux et d'Études Structurales (CEMES) , Centre National de la Recherche Scientifique (CNRS), Université de Toulouse , 29 Rue J. Marvig, BP 4347 , 31055 Toulouse , Cedex , France
| | - Carlos Manzano
- Institute of Material Research and Engineering (IMRE) , Agency for Science, Technology and Engineering (A*STAR), 3 Research Link , Singapore 117602 , Singapore
| | - Roberto Robles
- Centro de Física de Materiales CFM/MPC (CSIC-UPV/EHU) , Paseo Manuel de Lardizabal 5 , 20018 Donostia-San Sebastián , Spain
| | - Nicolas Lorente
- Centro de Física de Materiales CFM/MPC (CSIC-UPV/EHU) , Paseo Manuel de Lardizabal 5 , 20018 Donostia-San Sebastián , Spain
| | - Christian Joachim
- Centre d'Elaboration de Matériaux et d'Études Structurales (CEMES) , Centre National de la Recherche Scientifique (CNRS), Université de Toulouse , 29 Rue J. Marvig, BP 4347 , 31055 Toulouse , Cedex , France
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10
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Tuerhong R, Boero M, Bucher JP. Molecular attachment to a microscope tip: inelastic tunneling, Kondo screening, and thermopower. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2019; 10:1243-1250. [PMID: 31293862 PMCID: PMC6604733 DOI: 10.3762/bjnano.10.124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 06/06/2019] [Indexed: 06/09/2023]
Abstract
The vibrational excitation related transport properties of a manganese phthalocyanine molecule suspended between the tip of a scanning tunneling microsope (STM) and a surface are investigated by combining the local manipulation capabilities of the STM with inelastic electron tunneling spectroscopy. By attachment of the molecule to the probe tip, the intrinsic physical properties similar to those exhibited by a free standing molecule become accessible. This technique allows one to study locally the magnetic properties, as well as other elementary excitations and their mutual interaction. In particular a clear correlation is observed between the Kondo resonance and the vibrations with a strong incidence of the Kondo correlation on the thermopower measured across the single-molecule junction.
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Affiliation(s)
| | - Mauro Boero
- Université de Strasbourg, IPCMS UMR 70504, 67034 Strasbourg, France
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11
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Giessibl FJ. The qPlus sensor, a powerful core for the atomic force microscope. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2019; 90:011101. [PMID: 30709191 DOI: 10.1063/1.5052264] [Citation(s) in RCA: 135] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 12/25/2018] [Indexed: 05/27/2023]
Abstract
Atomic force microscopy (AFM) was introduced in 1986 and has since made its way into surface science, nanoscience, chemistry, biology, and material science as an imaging and manipulating tool with a rising number of applications. AFM can be employed in ambient and liquid environments as well as in vacuum and at low and ultralow temperatures. The technique is an offspring of scanning tunneling microscopy (STM), where the tunneling tip of the STM is replaced by using a force sensor with an attached tip. Measuring the tiny chemical forces that act between the tip and the sample is more difficult than measuring the tunneling current in STM. Therefore, even 30 years after the introduction of AFM, progress in instrumentation is substantial. Here, we focus on the core of the AFM, the force sensor with its tip and detection mechanism. Initially, force sensors were mainly micro-machined silicon cantilevers, mainly using optical methods to detect their deflection. The qPlus sensor, originally based on a quartz tuning fork and now custom built from quartz, is self-sensing by utilizing the piezoelectricity of quartz. The qPlus sensor allows us to perform STM and AFM in parallel, and the spatial resolution of its AFM channel has reached the subatomic level, exceeding the resolution of STM. Frequency modulation AFM (FM-AFM), where the frequency of an oscillating cantilever is altered by the gradient of the force that acts between the tip and the sample, has emerged over the years as the method that provides atomic and subatomic spatial resolution as well as force spectroscopy with sub-piconewton sensitivity. FM-AFM is precise; because of all physical observables, time and frequency can be measured by far with the greatest accuracy. By design, FM-AFM clearly separates conservative and dissipative interactions where conservative forces induce a frequency shift and dissipative interactions alter the power needed to maintain a constant oscillation amplitude of the cantilever. As it operates in a noncontact mode, it enables simultaneous AFM and STM measurements. The frequency stability of quartz and the small oscillation amplitudes that are possible with stiff quartz sensors optimize the signal to noise ratio. Here, we discuss the operating principles, the assembly of qPlus sensors, amplifiers, limiting factors, and applications. Applications encompass unprecedented subatomic spatial resolution, the measurement of forces that act in atomic manipulation, imaging and spectroscopy of spin-dependent forces, and atomic resolution of organic molecules, graphite, graphene, and oxides.
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Affiliation(s)
- Franz J Giessibl
- Institute of Experimental and Applied Physics, University of Regensburg, Universitätsstrasse 31, D-93040 Regensburg, Germany
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12
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Goronzy DP, Ebrahimi M, Rosei F, Fang Y, De Feyter S, Tait SL, Wang C, Beton PH, Wee ATS, Weiss PS, Perepichka DF. Supramolecular Assemblies on Surfaces: Nanopatterning, Functionality, and Reactivity. ACS NANO 2018; 12:7445-7481. [PMID: 30010321 DOI: 10.1021/acsnano.8b03513] [Citation(s) in RCA: 147] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Understanding how molecules interact to form large-scale hierarchical structures on surfaces holds promise for building designer nanoscale constructs with defined chemical and physical properties. Here, we describe early advances in this field and highlight upcoming opportunities and challenges. Both direct intermolecular interactions and those that are mediated by coordinated metal centers or substrates are discussed. These interactions can be additive, but they can also interfere with each other, leading to new assemblies in which electrical potentials vary at distances much larger than those of typical chemical interactions. Earlier spectroscopic and surface measurements have provided partial information on such interfacial effects. In the interim, scanning probe microscopies have assumed defining roles in the field of molecular organization on surfaces, delivering deeper understanding of interactions, structures, and local potentials. Self-assembly is a key strategy to form extended structures on surfaces, advancing nanolithography into the chemical dimension and providing simultaneous control at multiple scales. In parallel, the emergence of graphene and the resulting impetus to explore 2D materials have broadened the field, as surface-confined reactions of molecular building blocks provide access to such materials as 2D polymers and graphene nanoribbons. In this Review, we describe recent advances and point out promising directions that will lead to even greater and more robust capabilities to exploit designer surfaces.
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Affiliation(s)
- Dominic P Goronzy
- California NanoSystems Institute , University of California, Los Angeles , Los Angeles , California 90095 , United States
- Department of Chemistry and Biochemistry , University of California, Los Angeles , Los Angeles , California 90095 , United States
| | - Maryam Ebrahimi
- INRS Centre for Energy, Materials and Telecommunications , 1650 Boul. Lionel Boulet , Varennes , Quebec J3X 1S2 , Canada
| | - Federico Rosei
- INRS Centre for Energy, Materials and Telecommunications , 1650 Boul. Lionel Boulet , Varennes , Quebec J3X 1S2 , Canada
- Institute for Fundamental and Frontier Science , University of Electronic Science and Technology of China , Chengdu 610054 , P.R. China
| | - Yuan Fang
- Department of Chemistry , McGill University , Montreal H3A 0B8 , Canada
| | - Steven De Feyter
- Department of Chemistry , KU Leuven , Celestijnenlaan 200F , Leuven 3001 , Belgium
| | - Steven L Tait
- Department of Chemistry , Indiana University , Bloomington , Indiana 47405 , United States
| | - Chen Wang
- National Center for Nanoscience and Technology , Beijing 100190 , China
| | - Peter H Beton
- School of Physics & Astronomy , University of Nottingham , Nottingham NG7 2RD , United Kingdom
| | - Andrew T S Wee
- Department of Physics , National University of Singapore , 117542 Singapore
| | - Paul S Weiss
- California NanoSystems Institute , University of California, Los Angeles , Los Angeles , California 90095 , United States
- Department of Chemistry and Biochemistry , University of California, Los Angeles , Los Angeles , California 90095 , United States
- Department of Materials Science and Engineering , University of California, Los Angeles , Los Angeles , California 90095 , United States
| | - Dmitrii F Perepichka
- California NanoSystems Institute , University of California, Los Angeles , Los Angeles , California 90095 , United States
- Department of Chemistry , McGill University , Montreal H3A 0B8 , Canada
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13
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Koch M, Li Z, Nacci C, Kumagai T, Franco I, Grill L. How Structural Defects Affect the Mechanical and Electrical Properties of Single Molecular Wires. PHYSICAL REVIEW LETTERS 2018; 121:047701. [PMID: 30095964 DOI: 10.1103/physrevlett.121.047701] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 04/25/2018] [Indexed: 06/08/2023]
Abstract
We report how individual defects affect single graphene nanoribbons by scanning tunneling and atomic force microscopy pulling experiments simultaneously accessing their electrical and mechanical properties. The on-surface polymerization of the graphene nanoribbons is controlled by cooperative effects as theoretically suggested. Further, we find, with the help of atomistic simulations, that defects substantially vary the molecule-substrate coupling and drastically increase the flexibility of the graphene nanoribbons while keeping their desirable electronic properties intact.
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Affiliation(s)
- Matthias Koch
- Department of Physical Chemistry, Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, 14195 Berlin, Germany
| | - Zhi Li
- Department of Chemistry, University of Rochester, Rochester, New York 14627, USA
| | - Christophe Nacci
- Department of Physical Chemistry, Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, 14195 Berlin, Germany
- Department of Physical Chemistry, University of Graz, Heinrichstrasse 28, 8010 Graz, Austria
| | - Takashi Kumagai
- Department of Physical Chemistry, Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, 14195 Berlin, Germany
| | - Ignacio Franco
- Department of Chemistry, University of Rochester, Rochester, New York 14627, USA
| | - Leonhard Grill
- Department of Physical Chemistry, Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, 14195 Berlin, Germany
- Department of Physical Chemistry, University of Graz, Heinrichstrasse 28, 8010 Graz, Austria
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14
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van Vreumingen D, Tewari S, Verbeek F, van Ruitenbeek JM. Towards Controlled Single-Molecule Manipulation Using "Real-Time" Molecular Dynamics Simulation: A GPU Implementation. MICROMACHINES 2018; 9:E270. [PMID: 30424203 PMCID: PMC6187332 DOI: 10.3390/mi9060270] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Revised: 05/24/2018] [Accepted: 05/25/2018] [Indexed: 02/04/2023]
Abstract
Molecular electronics saw its birth with the idea to build electronic circuitry with single molecules as individual components. Even though commercial applications are still modest, it has served an important part in the study of fundamental physics at the scale of single atoms and molecules. It is now a routine procedure in many research groups around the world to connect a single molecule between two metallic leads. What is unknown is the nature of this coupling between the molecule and the leads. We have demonstrated recently (Tewari, 2018, Ph.D. Thesis) our new setup based on a scanning tunneling microscope, which can be used to controllably manipulate single molecules and atomic chains. In this article, we will present the extension of our molecular dynamic simulator attached to this system for the manipulation of single molecules in real time using a graphics processing unit (GPU). This will not only aid in controlled lift-off of single molecules, but will also provide details about changes in the molecular conformations during the manipulation. This information could serve as important input for theoretical models and for bridging the gap between the theory and experiments.
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Affiliation(s)
- Dyon van Vreumingen
- Huygens-Kamerlingh Onnes Laboratorium, Universiteit Leiden, 2333CA Leiden, The Netherlands.
- Leiden Insitute of Advanced Computer Science, Universiteit Leiden, 2333CA Leiden, The Netherlands.
| | - Sumit Tewari
- Huygens-Kamerlingh Onnes Laboratorium, Universiteit Leiden, 2333CA Leiden, The Netherlands.
| | - Fons Verbeek
- Leiden Insitute of Advanced Computer Science, Universiteit Leiden, 2333CA Leiden, The Netherlands.
| | - Jan M van Ruitenbeek
- Huygens-Kamerlingh Onnes Laboratorium, Universiteit Leiden, 2333CA Leiden, The Netherlands.
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15
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Temirov R, Green MFB, Friedrich N, Leinen P, Esat T, Chmielniak P, Sarwar S, Rawson J, Kögerler P, Wagner C, Rohlfing M, Tautz FS. Molecular Model of a Quantum Dot Beyond the Constant Interaction Approximation. PHYSICAL REVIEW LETTERS 2018; 120:206801. [PMID: 29864317 DOI: 10.1103/physrevlett.120.206801] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Indexed: 05/24/2023]
Abstract
We present a physically intuitive model of molecular quantum dots beyond the constant interaction approximation. It accurately describes their charging behavior and allows the extraction of important molecular properties that are otherwise experimentally inaccessible. The model is applied to data recorded with a noncontact atomic force microscope on three different molecules that act as a quantum dot when attached to the microscope tip. The results are in excellent agreement with first-principles simulations.
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Affiliation(s)
- Ruslan Temirov
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Matthew F B Green
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Niklas Friedrich
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Philipp Leinen
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Taner Esat
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Pawel Chmielniak
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
- Institute of Inorganic Chemistry, RWTH Aachen University, 52074 Aachen, Germany
- Peter Grünberg Institut (PGI-6), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Sidra Sarwar
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
- Institute of Inorganic Chemistry, RWTH Aachen University, 52074 Aachen, Germany
- Peter Grünberg Institut (PGI-6), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Jeff Rawson
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
- Institute of Inorganic Chemistry, RWTH Aachen University, 52074 Aachen, Germany
- Peter Grünberg Institut (PGI-6), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Paul Kögerler
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
- Institute of Inorganic Chemistry, RWTH Aachen University, 52074 Aachen, Germany
- Peter Grünberg Institut (PGI-6), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Christian Wagner
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Michael Rohlfing
- Institut für Festkörpertheorie, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany
| | - F Stefan Tautz
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
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16
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Chen J, Isshiki H, Baretzky C, Balashov T, Wulfhekel W. Abrupt Switching of Crystal Fields during Formation of Molecular Contacts. ACS NANO 2018; 12:3280-3286. [PMID: 29565560 DOI: 10.1021/acsnano.7b07927] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Magnetic molecules have the potential to be used as building blocks for bits in quantum computers. The spin states of the magnetic ion in the molecule can be represented by the effective spin Hamiltonian describing the zero field splitting (ZFS) of the magnetic states. We determined the ZFS of mechanically flexible metal-chelate molecules (Co, Ni, and Cu as metal ions) adsorbed on Cu2N/Cu(100) by inelastic tunneling spectroscopy at temperatures down to 30 mK. When moving the tip toward the molecule, the tunneling current abruptly jumps to higher values, indicating the sudden deformation of the molecule bridging the tunneling junction. Hand in hand with the formation of the contact, an abrupt change of the ZFS occurs. This work also implies that ZFS expected in mechanical break junctions can drastically deviate from that of adsorbed molecules probed by other techniques.
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Affiliation(s)
- Jinjie Chen
- Physikalisches Institut , Karlsruhe Institute of Technology (KIT) , Wolfgang-Gaede-Straße 1 , 76131 Karlsruhe , Germany
| | - Hironari Isshiki
- Physikalisches Institut , Karlsruhe Institute of Technology (KIT) , Wolfgang-Gaede-Straße 1 , 76131 Karlsruhe , Germany
| | - Clemens Baretzky
- Physikalisches Institut , Karlsruhe Institute of Technology (KIT) , Wolfgang-Gaede-Straße 1 , 76131 Karlsruhe , Germany
| | - Timofey Balashov
- Physikalisches Institut , Karlsruhe Institute of Technology (KIT) , Wolfgang-Gaede-Straße 1 , 76131 Karlsruhe , Germany
| | - Wulf Wulfhekel
- Physikalisches Institut , Karlsruhe Institute of Technology (KIT) , Wolfgang-Gaede-Straße 1 , 76131 Karlsruhe , Germany
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17
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Wang Y, Li X, Zheng X, Yang J. Manipulation of spin and magnetic anisotropy in bilayer magnetic molecular junctions. Phys Chem Chem Phys 2018; 20:26396-26404. [DOI: 10.1039/c8cp05759a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The Kondo effect and magnetic anisotropy in bilayer TMPc/TMPc/Pb(111) junctions can be actively tuned by changing the intermediate decoupling layer.
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Affiliation(s)
- Yu Wang
- Institute for Advanced Study
- Shenzhen University
- Shenzhen 518060
- China
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province
| | - Xiaoguang Li
- Institute for Advanced Study
- Shenzhen University
- Shenzhen 518060
- China
| | - Xiao Zheng
- Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics
- University of Science and Technology of China
- Hefei 230026
- China
| | - Jinlong Yang
- Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics
- University of Science and Technology of China
- Hefei 230026
- China
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18
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Li R, Li N, Wang H, Weismann A, Zhang Y, Hou S, Wu K, Wang Y. Tuning the spin-related transport properties of FePc on Au(111) through single-molecule chemistry. Chem Commun (Camb) 2018; 54:9135-9138. [PMID: 30059079 DOI: 10.1039/c8cc02994f] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Tuning the spin-related transport properties of FePc on Au(111) through single-molecule chemistry.
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Affiliation(s)
- Ruoning Li
- Key Laboratory for the Physics and Chemistry of Nanodevices
- Department of Electronics
- Peking University
- Beijing 100871
- China
| | - Na Li
- Key Laboratory for the Physics and Chemistry of Nanodevices
- Department of Electronics
- Peking University
- Beijing 100871
- China
| | - Hao Wang
- Key Laboratory for the Physics and Chemistry of Nanodevices
- Department of Electronics
- Peking University
- Beijing 100871
- China
| | - Alexander Weismann
- Institut für Experimentelle und Angewandte Physik
- Christian-Albrechts-Universität zu Kiel
- 24098 Kiel
- Germany
| | - Yajie Zhang
- Key Laboratory for the Physics and Chemistry of Nanodevices
- Department of Electronics
- Peking University
- Beijing 100871
- China
| | - Shimin Hou
- Key Laboratory for the Physics and Chemistry of Nanodevices
- Department of Electronics
- Peking University
- Beijing 100871
- China
| | - Kai Wu
- BNLMS
- College of Chemistry and Molecular Engineering
- Peking University
- Beijing 100871
- China
| | - Yongfeng Wang
- Key Laboratory for the Physics and Chemistry of Nanodevices
- Department of Electronics
- Peking University
- Beijing 100871
- China
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19
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Jasper-Tönnies T, Garcia-Lekue A, Frederiksen T, Ulrich S, Herges R, Berndt R. Conductance of a Freestanding Conjugated Molecular Wire. PHYSICAL REVIEW LETTERS 2017; 119:066801. [PMID: 28949604 DOI: 10.1103/physrevlett.119.066801] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Indexed: 06/07/2023]
Abstract
A freestanding molecular wire is placed vertically on Au(111) using a platform molecule and contacted by a scanning tunneling microscope. Despite the simplicity of the single-molecule junction, its conductance G reproducibly varies in a complex manner with the electrode separation. Transport calculations show that G is controlled by a deformation of the molecule, a symmetry mismatch between the tip and molecule orbitals, and the breaking of a C≡C triple in favor of a Au─C─C bond. This tip-controlled reversible bond formation or rupture alters the electronic spectrum of the junction and the states accessible for transport, resulting in an order of magnitude variation of the conductance.
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Affiliation(s)
- Torben Jasper-Tönnies
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
| | - Aran Garcia-Lekue
- Donostia International Physics Center, DIPC, Paseo Manuel de Lardizabal 4, E-20018 Donostia-San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, E-48013 Bilbao, Spain
| | - Thomas Frederiksen
- Donostia International Physics Center, DIPC, Paseo Manuel de Lardizabal 4, E-20018 Donostia-San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, E-48013 Bilbao, Spain
| | - Sandra Ulrich
- Otto-Diels-Institut für Organische Chemie, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
| | - Rainer Herges
- Otto-Diels-Institut für Organische Chemie, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
| | - Richard Berndt
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
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20
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Gaudenzi R, Misiorny M, Burzurí E, Wegewijs MR, van der Zant HSJ. Transport mirages in single-molecule devices. J Chem Phys 2017. [DOI: 10.1063/1.4975767] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Affiliation(s)
- R. Gaudenzi
- Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA Delft, The Netherlands
| | - M. Misiorny
- Department of Microtechnology and Nanoscience MC2, Chalmers University of Technology, 412 96 Göteborg, Sweden
- Faculty of Physics, Adam Mickiewicz University, 61-614 Poznań, Poland
| | - E. Burzurí
- Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA Delft, The Netherlands
| | - M. R. Wegewijs
- Peter Grünberg Institut, Forschungszentrum Jülich, 52425 Jülich, Germany
- JARA-FIT, 52056 Aachen, Germany
- Institute for Theory of Statistical Physics, RWTH Aachen, 52056 Aachen, Germany
| | - H. S. J. van der Zant
- Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA Delft, The Netherlands
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21
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Wang Y, Zheng X, Yang J. Kondo screening and spin excitation in few-layer CoPc molecular assembly stacking on Pb(111) surface: A DFT+HEOM study. J Chem Phys 2016; 145:154301. [DOI: 10.1063/1.4964675] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Affiliation(s)
- Yu Wang
- Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Xiao Zheng
- Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Jinlong Yang
- Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
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22
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Leinen P, Green MFB, Esat T, Wagner C, Tautz FS, Temirov R. Hand Controlled Manipulation of Single Molecules via a Scanning Probe Microscope with a 3D Virtual Reality Interface. J Vis Exp 2016. [PMID: 27768084 DOI: 10.3791/54506] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Considering organic molecules as the functional building blocks of future nanoscale technology, the question of how to arrange and assemble such building blocks in a bottom-up approach is still open. The scanning probe microscope (SPM) could be a tool of choice; however, SPM-based manipulation was until recently limited to two dimensions (2D). Binding the SPM tip to a molecule at a well-defined position opens an opportunity of controlled manipulation in 3D space. Unfortunately, 3D manipulation is largely incompatible with the typical 2D-paradigm of viewing and generating SPM data on a computer. For intuitive and efficient manipulation we therefore couple a low-temperature non-contact atomic force/scanning tunneling microscope (LT NC-AFM/STM) to a motion capture system and fully immersive virtual reality goggles. This setup permits "hand controlled manipulation" (HCM), in which the SPM tip is moved according to the motion of the experimenter's hand, while the tip trajectories as well as the response of the SPM junction are visualized in 3D. HCM paves the way to the development of complex manipulation protocols, potentially leading to a better fundamental understanding of nanoscale interactions acting between molecules on surfaces. Here we describe the setup and the steps needed to achieve successful hand-controlled molecular manipulation within the virtual reality environment.
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Affiliation(s)
- Philipp Leinen
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich; Fundamentals of Future Information Technology, Jülich Aachen Research Alliance (JARA)
| | - Matthew F B Green
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich; Fundamentals of Future Information Technology, Jülich Aachen Research Alliance (JARA)
| | - Taner Esat
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich; Fundamentals of Future Information Technology, Jülich Aachen Research Alliance (JARA)
| | - Christian Wagner
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich; Fundamentals of Future Information Technology, Jülich Aachen Research Alliance (JARA);
| | - F Stefan Tautz
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich; Fundamentals of Future Information Technology, Jülich Aachen Research Alliance (JARA)
| | - Ruslan Temirov
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich; Fundamentals of Future Information Technology, Jülich Aachen Research Alliance (JARA)
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23
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Xie Z, Shi S, Liu F, Smith DL, Ruden PP, Frisbie CD. Large Magnetoresistance at Room Temperature in Organic Molecular Tunnel Junctions with Nonmagnetic Electrodes. ACS NANO 2016. [PMID: 27598057 DOI: 10.1103/physrevb.95.155315] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
We report room-temperature resistance changes of up to 30% under weak magnetic fields (0.1 T) for molecular tunnel junctions composed of oligophenylene thiol molecules, 1-2 nm in length, sandwiched between gold contacts. The magnetoresistance (MR) is independent of field orientation and the length of the molecule; it appears to be an interface effect. Theoretical analysis suggests that the source of the MR is a two-carrier (two-hole) interaction at the interface, resulting in spin coupling between the tunneling hole and a localized hole at the Au/molecule contact. Such coupling leads to significantly different singlet and triplet transmission barriers at the interface. Even weak magnetic fields impede spin relaxation processes and thus modify the ratio of holes tunneling via the singlet state versus the triplet state, which leads to the large MR. Overall, the experiments and analysis suggest significant opportunities to explore large MR effects in molecular tunnel junctions based on widely available molecules.
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Affiliation(s)
- Zuoti Xie
- Department of Chemical Engineering and Materials Science and ‡Department of Electrical and Computer Engineering, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Sha Shi
- Department of Chemical Engineering and Materials Science and ‡Department of Electrical and Computer Engineering, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Feilong Liu
- Department of Chemical Engineering and Materials Science and ‡Department of Electrical and Computer Engineering, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Darryl L Smith
- Department of Chemical Engineering and Materials Science and ‡Department of Electrical and Computer Engineering, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - P Paul Ruden
- Department of Chemical Engineering and Materials Science and ‡Department of Electrical and Computer Engineering, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - C Daniel Frisbie
- Department of Chemical Engineering and Materials Science and ‡Department of Electrical and Computer Engineering, University of Minnesota , Minneapolis, Minnesota 55455, United States
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24
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Xie Z, Shi S, Liu F, Smith DL, Ruden PP, Frisbie CD. Large Magnetoresistance at Room Temperature in Organic Molecular Tunnel Junctions with Nonmagnetic Electrodes. ACS NANO 2016; 10:8571-7. [PMID: 27598057 DOI: 10.1021/acsnano.6b03853] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
We report room-temperature resistance changes of up to 30% under weak magnetic fields (0.1 T) for molecular tunnel junctions composed of oligophenylene thiol molecules, 1-2 nm in length, sandwiched between gold contacts. The magnetoresistance (MR) is independent of field orientation and the length of the molecule; it appears to be an interface effect. Theoretical analysis suggests that the source of the MR is a two-carrier (two-hole) interaction at the interface, resulting in spin coupling between the tunneling hole and a localized hole at the Au/molecule contact. Such coupling leads to significantly different singlet and triplet transmission barriers at the interface. Even weak magnetic fields impede spin relaxation processes and thus modify the ratio of holes tunneling via the singlet state versus the triplet state, which leads to the large MR. Overall, the experiments and analysis suggest significant opportunities to explore large MR effects in molecular tunnel junctions based on widely available molecules.
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Affiliation(s)
- Zuoti Xie
- Department of Chemical Engineering and Materials Science and ‡Department of Electrical and Computer Engineering, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Sha Shi
- Department of Chemical Engineering and Materials Science and ‡Department of Electrical and Computer Engineering, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Feilong Liu
- Department of Chemical Engineering and Materials Science and ‡Department of Electrical and Computer Engineering, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Darryl L Smith
- Department of Chemical Engineering and Materials Science and ‡Department of Electrical and Computer Engineering, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - P Paul Ruden
- Department of Chemical Engineering and Materials Science and ‡Department of Electrical and Computer Engineering, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - C Daniel Frisbie
- Department of Chemical Engineering and Materials Science and ‡Department of Electrical and Computer Engineering, University of Minnesota , Minneapolis, Minnesota 55455, United States
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25
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Okuyama H, Kitaguchi Y, Hattori T, Ueda Y, Ferrer NG, Hatta S, Aruga T. Adsorbed states of chlorophenol on Cu(110) and controlled switching of single-molecule junctions. J Chem Phys 2016; 144:244703. [PMID: 27369529 DOI: 10.1063/1.4954409] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
A molecular junction of substituted benzene (chlorophenol) is fabricated and controlled by using a scanning tunneling microscope (STM). Prior to the junction formation, the bonding geometry of the molecule on the surface is characterized by STM and electron energy loss spectroscopy (EELS). EELS shows that the OH group of chlorophenol is dissociated on Cu(110) and that the molecule is bonded nearly flat to the surface via an O atom, with the Cl group intact. We demonstrate controlled contact of an STM tip to the "available" Cl group and lift-up of the molecule while it is anchored to the surface via an O atom. The asymmetric bonding motifs of the molecule to the electrodes allow for reversible control of the junction.
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Affiliation(s)
- H Okuyama
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Y Kitaguchi
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - T Hattori
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Y Ueda
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - N G Ferrer
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - S Hatta
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - T Aruga
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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26
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Requist R, Baruselli PP, Smogunov A, Fabrizio M, Modesti S, Tosatti E. Metallic, magnetic and molecular nanocontacts. NATURE NANOTECHNOLOGY 2016; 11:499-508. [PMID: 27272139 DOI: 10.1038/nnano.2016.55] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 03/08/2016] [Indexed: 06/06/2023]
Abstract
Scanning tunnelling microscopy and break-junction experiments realize metallic and molecular nanocontacts that act as ideal one-dimensional channels between macroscopic electrodes. Emergent nanoscale phenomena typical of these systems encompass structural, mechanical, electronic, transport, and magnetic properties. This Review focuses on the theoretical explanation of some of these properties obtained with the help of first-principles methods. By tracing parallel theoretical and experimental developments from the discovery of nanowire formation and conductance quantization in gold nanowires to recent observations of emergent magnetism and Kondo correlations, we exemplify the main concepts and ingredients needed to bring together ab initio calculations and physical observations. It can be anticipated that diode, sensor, spin-valve and spin-filter functionalities relevant for spintronics and molecular electronics applications will benefit from the physical understanding thus obtained.
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Affiliation(s)
- Ryan Requist
- International School for Advanced Studies (SISSA), Via Bonomea 265, Trieste 34136, Italy
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06114 Halle, Germany
| | - Pier Paolo Baruselli
- International School for Advanced Studies (SISSA), Via Bonomea 265, Trieste 34136, Italy
- Institut für Theoretische Physik, Technische Universität Dresden, 01062 Dresden, Germany
- Democritos Simulation Center, Istituto Officina dei Materiali, Consiglio Nazionale delle Ricerche, Via Bonomea 265, Trieste 34136, Italy
| | - Alexander Smogunov
- Service de Physique de l'Etat Condensé (SPEC), CEA, CNRS, Université Paris-Saclay, CEA Saclay 91191 Gif-sur-Yvette Cedex, France
| | - Michele Fabrizio
- International School for Advanced Studies (SISSA), Via Bonomea 265, Trieste 34136, Italy
- Democritos Simulation Center, Istituto Officina dei Materiali, Consiglio Nazionale delle Ricerche, Via Bonomea 265, Trieste 34136, Italy
| | - Silvio Modesti
- Physics Department, University of Trieste, Via Valerio 2, Trieste 34127, Italy
- TASC Laboratory, Istituto Officina dei Materiali, Consiglio Nazionale delle Ricerche, s.s. 14 km 163.5, Trieste 34149, Italy
| | - Erio Tosatti
- International School for Advanced Studies (SISSA), Via Bonomea 265, Trieste 34136, Italy
- Democritos Simulation Center, Istituto Officina dei Materiali, Consiglio Nazionale delle Ricerche, Via Bonomea 265, Trieste 34136, Italy
- International Centre for Theoretical Physics (ICTP), Strada Costiera 11, Trieste 34151, Italy
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27
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Rakhmilevitch D, Tal O. Vibration-mediated Kondo transport in molecular junctions: conductance evolution during mechanical stretching. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2015; 6:2417-22. [PMID: 26734532 PMCID: PMC4685914 DOI: 10.3762/bjnano.6.249] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 11/17/2015] [Indexed: 06/05/2023]
Abstract
The vibration-mediated Kondo effect attracted considerable theoretical interest during the last decade. However, due to lack of extensive experimental demonstrations, the fine details of the phenomenon were not addressed. Here, we analyze the evolution of vibration-mediated Kondo effect in molecular junctions during mechanical stretching. The described analysis reveals the different contributions of Kondo and inelastic transport.
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Affiliation(s)
- David Rakhmilevitch
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Oren Tal
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot, Israel
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28
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Kitaguchi Y, Habuka S, Okuyama H, Hatta S, Aruga T, Frederiksen T, Paulsson M, Ueba H. Controlled switching of single-molecule junctions by mechanical motion of a phenyl ring. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2015; 6:2088-95. [PMID: 26665080 PMCID: PMC4660945 DOI: 10.3762/bjnano.6.213] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 10/21/2015] [Indexed: 06/05/2023]
Abstract
Mechanical methods for single-molecule control have potential for wide application in nanodevices and machines. Here we demonstrate the operation of a single-molecule switch made functional by the motion of a phenyl ring, analogous to the lever in a conventional toggle switch. The switch can be actuated by dual triggers, either by a voltage pulse or by displacement of the electrode, and electronic manipulation of the ring by chemical substitution enables rational control of the on-state conductance. Owing to its simple mechanics, structural robustness, and chemical accessibility, we propose that phenyl rings are promising components in mechanical molecular devices.
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Affiliation(s)
- Yuya Kitaguchi
- Department of Chemistry, Graduate School of Science, Kyoto University, 606-8502 Kyoto, Japan
| | - Satoru Habuka
- Department of Chemistry, Graduate School of Science, Kyoto University, 606-8502 Kyoto, Japan
| | - Hiroshi Okuyama
- Department of Chemistry, Graduate School of Science, Kyoto University, 606-8502 Kyoto, Japan
| | - Shinichiro Hatta
- Department of Chemistry, Graduate School of Science, Kyoto University, 606-8502 Kyoto, Japan
| | - Tetsuya Aruga
- Department of Chemistry, Graduate School of Science, Kyoto University, 606-8502 Kyoto, Japan
| | - Thomas Frederiksen
- Donostia International Physics Center (DIPC), 20018 San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain
| | - Magnus Paulsson
- School of Computer Science, Physics and Mathematics, Linnaeus University, 391 82 Kalmar, Sweden
| | - Hiromu Ueba
- Division of Nano and New Functional Materials Science, Graduate School of Science and Engineering, University of Toyama, 930-8555 Toyama, Japan
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29
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Reecht G, Bulou H, Scheurer F, Speisser V, Mathevet F, González C, Dappe YJ, Schull G. Pulling and Stretching a Molecular Wire to Tune its Conductance. J Phys Chem Lett 2015; 6:2987-2992. [PMID: 26267192 DOI: 10.1021/acs.jpclett.5b01283] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A scanning tunnelling microscope is used to pull a polythiophene wire from a Au(111) surface while measuring the current traversing the junction. Abrupt current increases measured during the lifting procedure are associated with the detachment of molecular subunits, in apparent contradiction with the expected exponential decrease of the conductance with wire length. Ab initio simulations reproduce the experimental data and demonstrate that this unexpected behavior is due to release of mechanical stress in the wire, paving the way to mechanically gated single-molecule electronic devices.
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Affiliation(s)
- Gaël Reecht
- †IPCMS de Strasbourg, UMR 7504 (CNRS - Université de Strasbourg), 67034 Strasbourg, France
| | - Hervé Bulou
- †IPCMS de Strasbourg, UMR 7504 (CNRS - Université de Strasbourg), 67034 Strasbourg, France
| | - Fabrice Scheurer
- †IPCMS de Strasbourg, UMR 7504 (CNRS - Université de Strasbourg), 67034 Strasbourg, France
| | - Virginie Speisser
- †IPCMS de Strasbourg, UMR 7504 (CNRS - Université de Strasbourg), 67034 Strasbourg, France
| | - Fabrice Mathevet
- ‡Institut Parisien de Chimie Moléculaire, Chimie des Polymères, UMR 8232, (CNRS - Université Pierre et Marie Curie), 75252 Paris, France
| | - César González
- §Service de Physique de l'Etat Condensé, DSM/IRAMIS/SPEC, CNRS UMR 3680, CEA Saclay, 91191 Gif sur Yvette cedex, France
| | - Yannick J Dappe
- §Service de Physique de l'Etat Condensé, DSM/IRAMIS/SPEC, CNRS UMR 3680, CEA Saclay, 91191 Gif sur Yvette cedex, France
| | - Guillaume Schull
- †IPCMS de Strasbourg, UMR 7504 (CNRS - Université de Strasbourg), 67034 Strasbourg, France
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30
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Inkpen MS, Lemmer M, Fitzpatrick N, Milan DC, Nichols RJ, Long NJ, Albrecht T. New Insights into Single-Molecule Junctions Using a Robust, Unsupervised Approach to Data Collection and Analysis. J Am Chem Soc 2015; 137:9971-81. [DOI: 10.1021/jacs.5b05693] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Michael S. Inkpen
- Department
of Chemistry, Imperial College London, London SW7 2AZ, U.K
| | - Mario Lemmer
- Department
of Chemistry, Imperial College London, London SW7 2AZ, U.K
| | | | - David C. Milan
- Department
of Chemistry, University of Liverpool, Liverpool L69 7ZD, U.K
| | - Richard J. Nichols
- Department
of Chemistry, University of Liverpool, Liverpool L69 7ZD, U.K
| | - Nicholas J. Long
- Department
of Chemistry, Imperial College London, London SW7 2AZ, U.K
| | - Tim Albrecht
- Department
of Chemistry, Imperial College London, London SW7 2AZ, U.K
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31
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Conductance of a single flexible molecular wire composed of alternating donor and acceptor units. Nat Commun 2015; 6:7397. [PMID: 26145188 PMCID: PMC4507002 DOI: 10.1038/ncomms8397] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 05/05/2015] [Indexed: 11/08/2022] Open
Abstract
Molecular-scale electronics is mainly concerned by understanding charge transport through individual molecules. A key issue here is the charge transport capability through a single--typically linear--molecule, characterized by the current decay with increasing length. To improve the conductance of individual polymers, molecular design often either involves the use of rigid ribbon/ladder-type structures, thereby sacrificing for flexibility of the molecular wire, or a zero band gap, typically associated with chemical instability. Here we show that a conjugated polymer composed of alternating donor and acceptor repeat units, synthesized directly by an on-surface polymerization, exhibits a very high conductance while maintaining both its flexible structure and a finite band gap. Importantly, electronic delocalization along the wire does not seem to be necessary as proven by spatial mapping of the electronic states along individual molecular wires. Our approach should facilitate the realization of flexible 'soft' molecular-scale circuitry, for example, on bendable substrates.
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32
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Controlling single-molecule junction conductance by molecular interactions. Sci Rep 2015; 5:11796. [PMID: 26135251 PMCID: PMC4488765 DOI: 10.1038/srep11796] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 06/05/2015] [Indexed: 11/08/2022] Open
Abstract
For the rational design of single-molecular electronic devices, it is essential to understand environmental effects on the electronic properties of a working molecule. Here we investigate the impact of molecular interactions on the single-molecule conductance by accurately positioning individual molecules on the electrode. To achieve reproducible and precise conductivity measurements, we utilize relatively weak π-bonding between a phenoxy molecule and a STM-tip to form and cleave one contact to the molecule. The anchoring to the other electrode is kept stable using a chalcogen atom with strong bonding to a Cu(110) substrate. These non-destructive measurements permit us to investigate the variation in single-molecule conductance under different but controlled environmental conditions. Combined with density functional theory calculations, we clarify the role of the electrostatic field in the environmental effect that influences the molecular level alignment.
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33
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Su TA, Li H, Steigerwald ML, Venkataraman L, Nuckolls C. Stereoelectronic switching in single-molecule junctions. Nat Chem 2015; 7:215-20. [PMID: 25698330 DOI: 10.1038/nchem.2180] [Citation(s) in RCA: 117] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Accepted: 01/09/2015] [Indexed: 11/09/2022]
Abstract
A new intersection between reaction chemistry and electronic circuitry is emerging from the ultraminiaturization of electronic devices. Over decades chemists have developed a nuanced understanding of stereoelectronics to establish how the electronic properties of molecules relate to their conformation; the recent advent of single-molecule break-junction techniques provides the means to alter this conformation with a level of control previously unimagined. Here we unite these ideas by demonstrating the first single-molecule switch that operates through a stereoelectronic effect. We demonstrate this behaviour in permethyloligosilanes with methylthiomethyl electrode linkers. The strong σ conjugation in the oligosilane backbone couples the stereoelectronic properties of the sulfur-methylene σ bonds that terminate the molecule. Theoretical calculations support the existence of three distinct dihedral conformations that differ drastically in their electronic character. We can shift between these three species by simply lengthening or compressing the molecular junction, and, in doing so, we can switch conductance digitally between two states.
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Affiliation(s)
- Timothy A Su
- Department of Chemistry, Columbia University, New York 10027, USA
| | - Haixing Li
- Department of Applied Physics, Columbia University, New York 10027, USA
| | | | | | - Colin Nuckolls
- Department of Chemistry, Columbia University, New York 10027, USA
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34
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Leinen P, Green MFB, Esat T, Wagner C, Tautz FS, Temirov R. Virtual reality visual feedback for hand-controlled scanning probe microscopy manipulation of single molecules. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2015; 6:2148-53. [PMID: 26665087 PMCID: PMC4660913 DOI: 10.3762/bjnano.6.220] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 10/28/2015] [Indexed: 05/05/2023]
Abstract
Controlled manipulation of single molecules is an important step towards the fabrication of single molecule devices and nanoscale molecular machines. Currently, scanning probe microscopy (SPM) is the only technique that facilitates direct imaging and manipulations of nanometer-sized molecular compounds on surfaces. The technique of hand-controlled manipulation (HCM) introduced recently in Beilstein J. Nanotechnol. 2014, 5, 1926-1932 simplifies the identification of successful manipulation protocols in situations when the interaction pattern of the manipulated molecule with its environment is not fully known. Here we present a further technical development that substantially improves the effectiveness of HCM. By adding Oculus Rift virtual reality goggles to our HCM set-up we provide the experimentalist with 3D visual feedback that displays the currently executed trajectory and the position of the SPM tip during manipulation in real time, while simultaneously plotting the experimentally measured frequency shift (Δf) of the non-contact atomic force microscope (NC-AFM) tuning fork sensor as well as the magnitude of the electric current (I) flowing between the tip and the surface. The advantages of the set-up are demonstrated by applying it to the model problem of the extraction of an individual PTCDA molecule from its hydrogen-bonded monolayer grown on Ag(111) surface.
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Affiliation(s)
- Philipp Leinen
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Matthew F B Green
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Taner Esat
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Christian Wagner
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - F Stefan Tautz
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Ruslan Temirov
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
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35
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Wagner C, Fournier N, Ruiz VG, Li C, Müllen K, Rohlfing M, Tkatchenko A, Temirov R, Tautz FS. Non-additivity of molecule-surface van der Waals potentials from force measurements. Nat Commun 2014; 5:5568. [PMID: 25424490 PMCID: PMC4263323 DOI: 10.1038/ncomms6568] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 10/14/2014] [Indexed: 11/16/2022] Open
Abstract
Van der Waals (vdW) forces act ubiquitously in condensed matter. Despite being weak on an atomic level, they substantially influence molecular and biological systems due to their long range and system-size scaling. The difficulty to isolate and measure vdW forces on a single-molecule level causes our present understanding to be strongly theory based. Here we show measurements of the attractive potential between differently sized organic molecules and a metal surface using an atomic force microscope. Our choice of molecules and the large molecule-surface separation cause this attraction to be purely of vdW type. The experiment allows testing the asymptotic vdW force law and its validity range. We find a superlinear growth of the vdW attraction with molecular size, originating from the increased deconfinement of electrons in the molecules. Because such non-additive vdW contributions are not accounted for in most first-principles or empirical calculations, we suggest further development in that direction. Van der Waals interactions are difficult to calculate at an atomistic level for moderate sized structures due to the many distinct atoms involved. Here, the authors measure the van der Waals force between an organic molecule and a metal surface, examining the non-additive part of these interactions.
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Affiliation(s)
- Christian Wagner
- 1] Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany [2] Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Norman Fournier
- 1] Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany [2] Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Victor G Ruiz
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - Chen Li
- Max-Planck-Institut für Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany
| | - Klaus Müllen
- Max-Planck-Institut für Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany
| | - Michael Rohlfing
- Institut für Festkörpertheorie der Universität Münster, Wilhelm-Klemm-Straße 10, 48149 Münster, Germany
| | - Alexandre Tkatchenko
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - Ruslan Temirov
- 1] Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany [2] Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - F Stefan Tautz
- 1] Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany [2] Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
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36
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Wang Y, Zheng X, Li B, Yang J. Understanding the Kondo resonance in the d-CoPc/Au(111) adsorption system. J Chem Phys 2014; 141:084713. [DOI: 10.1063/1.4893953] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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37
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Wagner C, Fournier N, Tautz FS, Temirov R. The role of surface corrugation and tip oscillation in single-molecule manipulation with a non-contact atomic force microscope. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2014; 5:202-9. [PMID: 24605287 PMCID: PMC3943512 DOI: 10.3762/bjnano.5.22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 01/31/2014] [Indexed: 05/05/2023]
Abstract
Scanning probe microscopy (SPM) plays an important role in the investigation of molecular adsorption. The possibility to probe the molecule-surface interaction while tuning its strength through SPM tip-induced single-molecule manipulation has particularly promising potential to yield new insights. We recently reported experiments, in which 3,4,9,10-perylene-tetracarboxylic-dianhydride (PTCDA) molecules were lifted with a qPlus-sensor and analyzed these experiments by using force-field simulations. Irrespective of the good agreement between the experiment and those simulations, systematic inconsistencies remained that we attribute to effects omitted from the initial model. Here we develop a more realistic simulation of single-molecule manipulation by non-contact AFM that includes the atomic surface corrugation, the tip elasticity, and the tip oscillation amplitude. In short, we simulate a full tip oscillation cycle at each step of the manipulation process and calculate the frequency shift by solving the equation of motion of the tip. The new model correctly reproduces previously unexplained key features of the experiment, and facilitates a better understanding of the mechanics of single-molecular junctions. Our simulations reveal that the surface corrugation adds a positive frequency shift to the measurement that generates an apparent repulsive force. Furthermore, we demonstrate that the scatter observed in the experimental data points is related to the sliding of the molecule across the surface.
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Affiliation(s)
- Christian Wagner
- Leiden Institute of Physics, Universiteit Leiden, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Norman Fournier
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - F Stefan Tautz
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Ruslan Temirov
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
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38
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Green MFB, Esat T, Wagner C, Leinen P, Grötsch A, Tautz FS, Temirov R. Patterning a hydrogen-bonded molecular monolayer with a hand-controlled scanning probe microscope. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2014; 5:1926-32. [PMID: 25383304 PMCID: PMC4222388 DOI: 10.3762/bjnano.5.203] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 10/10/2014] [Indexed: 05/05/2023]
Abstract
One of the paramount goals in nanotechnology is molecular-scale functional design, which includes arranging molecules into complex structures at will. The first steps towards this goal were made through the invention of the scanning probe microscope (SPM), which put single-atom and single-molecule manipulation into practice for the first time. Extending the controlled manipulation to larger molecules is expected to multiply the potential of engineered nanostructures. Here we report an enhancement of the SPM technique that makes the manipulation of large molecular adsorbates much more effective. By using a commercial motion tracking system, we couple the movements of an operator's hand to the sub-angstrom precise positioning of an SPM tip. Literally moving the tip by hand we write a nanoscale structure in a monolayer of large molecules, thereby showing that our method allows for the successful execution of complex manipulation protocols even when the potential energy surface that governs the interaction behaviour of the manipulated nanoscale object(s) is largely unknown.
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Affiliation(s)
- Matthew F B Green
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Taner Esat
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Christian Wagner
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
- Leiden Institute of Physics, Universiteit Leiden, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands
| | - Philipp Leinen
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Alexander Grötsch
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
- Unit Human Factors, Ergonomics, Federal Institute for Occupational Safety and Health (BAuA), 44149 Dortmund, Germany
| | - F Stefan Tautz
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Ruslan Temirov
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany
- Jülich Aachen Research Alliance (JARA)-Fundamentals of Future Information Technology, 52425 Jülich, Germany
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39
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Zhang YH, Kahle S, Herden T, Stroh C, Mayor M, Schlickum U, Ternes M, Wahl P, Kern K. Temperature and magnetic field dependence of a Kondo system in the weak coupling regime. Nat Commun 2013; 4:2110. [PMID: 23817525 PMCID: PMC3730050 DOI: 10.1038/ncomms3110] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 06/06/2013] [Indexed: 11/09/2022] Open
Abstract
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 comparison with theoretical predictions remained challenging. Here we show that the zero-bias anomaly detected on an organic radical weakly coupled to a Au (111) surface can be described with astonishing agreement by perturbation theory as originally developed by Kondo 60 years ago. Our results demonstrate that Kondo physics can only be fully conceived by studying both temperature and magnetic field dependence of the resonance. The identification of a spin 1/2 Kondo system is of relevance not only as a benchmark for predictions for Kondo physics but also for correlated electron materials in general.
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Affiliation(s)
- Yong-hui Zhang
- Max-Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany
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40
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Koch M, Ample F, Joachim C, Grill L. Voltage-dependent conductance of a single graphene nanoribbon. NATURE NANOTECHNOLOGY 2012; 7:713-7. [PMID: 23064554 DOI: 10.1038/nnano.2012.169] [Citation(s) in RCA: 172] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2012] [Accepted: 09/03/2012] [Indexed: 05/22/2023]
Abstract
Graphene nanoribbons could potentially be used to create molecular wires with tailored conductance properties. However, understanding charge transport through a single molecule requires length-dependent conductance measurements and a systematic variation of the electrode potentials relative to the electronic states of the molecule. Here, we show that the conductance properties of a single molecule can be correlated with its electronic states. Using a scanning tunnelling microscope, the electronic structure of a long and narrow graphene nanoribbon, which is adsorbed on a Au(111) surface, is spatially mapped and its conductance then measured by lifting the molecule off the surface with the tip of the microscope. The tunnelling decay length is measured over a wide range of bias voltages, from the localized Tamm states over the gap up to the delocalized occupied and unoccupied electronic states of the nanoribbon. We also show how the conductance depends on the precise atomic structure and bending of the molecule in the junction, illustrating the importance of the edge states and a planar geometry.
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Affiliation(s)
- Matthias Koch
- Department of Physical Chemistry, Fritz-Haber-Institute of the Max-Planck-Society, 14195 Berlin, Germany
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41
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Wagner C, Fournier N, Tautz FS, Temirov R. Measurement of the binding energies of the organic-metal perylene-teracarboxylic-dianhydride/Au111 bonds by molecular manipulation using an atomic force microscope. PHYSICAL REVIEW LETTERS 2012; 109:076102. [PMID: 23006386 DOI: 10.1103/physrevlett.109.076102] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Indexed: 05/22/2023]
Abstract
Based on single molecule manipulation experiments in a combined scanning tunneling microscope/frequency modulated atomic force microscope, we quantify the individual binding energy contributions to an organic-metal bond experimentally. The method allows the determination of contributions from, e.g., local chemical bonds, metal-molecule hybridization, and van der Waals interactions, as well as the total adsorption energy.
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Affiliation(s)
- C Wagner
- Peter Grünberg Institut, Forschungszentrum Jülich, Germany.
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42
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Kumar A, Heimbuch R, Poelsema B, Zandvliet HJW. Controlled transport through a single molecule. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:082201. [PMID: 22311709 DOI: 10.1088/0953-8984/24/8/082201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We demonstrate how an electrode-molecule-electrode junction can be controllably opened and closed by careful tuning of the contacts' interspace and voltage. The molecule, an octanethiol, flips to bridge a ~1 nm interspace between substrate and scanning tunnelling microscope tip when an electric field exceeds a threshold (switch 'on'). Reducing the field below this threshold value leads to the reproducible detachment of the octanethiol (switch 'off'). Once contacted, a further reduction of the contacts' interspace leads to an increase of the conductance of the molecule.
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Affiliation(s)
- A Kumar
- Physics of Interfaces and Nanomaterials, MESAC Institute for Nanotechnology, University of Twente, Enschede, The Netherlands
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43
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Kumar A, Heimbuch R, Wimbush KS, Ateşçi H, Acun A, Reinhoudt DN, Velders AH, Zandvliet HJW. Electron-induced dynamics of heptathioether β-cyclodextrin molecules. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2012; 8:317-322. [PMID: 22102562 DOI: 10.1002/smll.201101484] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Revised: 09/26/2011] [Indexed: 05/31/2023]
Abstract
Variable-temperature scanning tunneling microscopy (STM) and spectroscopy (STS) measurements are performed on heptathioether β-cyclodextrin (β-CD) self-assembled monolayers (SAMs) on Au. The β-CD molecules exhibit very rich dynamical behavior, which is not apparent in ensemble-averaged studies. The dynamics are reflected in the tunneling current-time traces, which are recorded with the STM feedback loop disabled. The dynamics are temperature independent, but increase with increasing tunneling current and sample bias, thus indicating that the conformational changes of the β-CD molecules are induced by electrons that tunnel inelastically. Even for sample biases as low as 10 mV, well-defined levels are observed in the tunneling current-time traces. These jumps are attributed to the excitations of the molecular vibration of the macrocyclic β-CD molecule. The results are of great importance for a proper understanding of transport measurements in SAMs.
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Affiliation(s)
- Avijit Kumar
- Physics of Interfaces and Nanomaterials, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
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44
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Fernández-Torrente I, Kreikemeyer-Lorenzo D, Stróżecka A, Franke KJ, Pascual JI. Gating the charge state of single molecules by local electric fields. PHYSICAL REVIEW LETTERS 2012; 108:036801. [PMID: 22400769 DOI: 10.1103/physrevlett.108.036801] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Indexed: 05/31/2023]
Abstract
The electron-acceptor molecule TCNQ is found in either of two distinct integer charge states when embedded into a monolayer of a charge transfer complex on a gold surface. Scanning tunneling spectroscopy measurements identify these states through the presence or absence of a zero-bias Kondo resonance. Increasing the (tip-induced) electric field allows us to reversibly induce the oxidation or reduction of TCNQ species from their anionic or neutral ground state, respectively. We show that the different ground states arise from slight variations in the underlying surface potential, pictured here as the gate of a three-terminal device.
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Affiliation(s)
- I Fernández-Torrente
- Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
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45
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Schull G, Dappe YJ, González C, Bulou H, Berndt R. Charge injection through single and double carbon bonds. NANO LETTERS 2011; 11:3142-3146. [PMID: 21761854 DOI: 10.1021/nl201185y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The contact conductance of oriented C(60) molecules is probed with a scanning tunneling microscope as a function of the lateral position of the tip in contact to the molecular cage. Together with first principles calculations, these measurements reveal variations of the efficiency of charge injection to the fullerene molecule with the order of the contacted carbon-carbon bond.
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Affiliation(s)
- Guillaume Schull
- Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504 (CNRS- Université de Strasbourg ), 67034 Strasbourg, France.
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46
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Leary E, González MT, van der Pol C, Bryce MR, Filippone S, Martín N, Rubio-Bollinger G, Agraït N. Unambiguous one-molecule conductance measurements under ambient conditions. NANO LETTERS 2011; 11:2236-2241. [PMID: 21548597 DOI: 10.1021/nl200294s] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
One of the challenging goals of molecular electronics is to wire exactly one molecule between two electrodes. This is generally nontrivial under ambient conditions. We describe a new and straightforward protocol for unambiguously isolating a single organic molecule on a metal surface and wiring it inside a nanojunction under ambient conditions. Our strategy employs C(60) terminal groups which act as molecular beacons allowing molecules to be visualized and individually targeted on a gold surface using an scanning tunneling microscope. After isolating one molecule, we then use the C(60) groups as alligator clips to wire it between the tip and surface. Once wired, we can monitor how the conductance of a purely one molecule junction evolves with time, stretch the molecule in the junction, observing characteristic current plateaus upon elongation, and also perform direct I-V spectroscopy. By characterizing and controlling the junction, we can draw stronger conclusions about the observed variation in molecular conductance than was previously possible.
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Affiliation(s)
- Edmund Leary
- Instituto Madrileño de Estudios Avanzados, Facultad de Ciencias Módulo 9, 3a planta Avda. Fco. Tomás y Valiente, 7 Ciudad Universitaria de Cantoblanco, 28049, Madrid, Spain.
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47
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Diez-Perez I, Hihath J, Hines T, Wang ZS, Zhou G, Müllen K, Tao N. Controlling single-molecule conductance through lateral coupling of π orbitals. NATURE NANOTECHNOLOGY 2011; 6:226-231. [PMID: 21336268 DOI: 10.1038/nnano.2011.20] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Accepted: 01/25/2011] [Indexed: 05/27/2023]
Abstract
In recent years, various single-molecule electronic components have been demonstrated. However, it remains difficult to predict accurately the conductance of a single molecule and to control the lateral coupling between the π orbitals of the molecule and the orbitals of the electrodes attached to it. This lateral coupling is well known to cause broadening and shifting of the energy levels of the molecule; this, in turn, is expected to greatly modify the conductance of an electrode-molecule-electrode junction. Here, we demonstrate a new method, based on lateral coupling, to mechanically and reversibly control the conductance of a single-molecule junction by mechanically modulating the angle between a single pentaphenylene molecule bridged between two metal electrodes. Changing the angle of the molecule from a highly tilted state to an orientation nearly perpendicular to the electrodes changes the conductance by an order of magnitude, which is in qualitative agreement with theoretical models of molecular π-orbital coupling to a metal electrode. The lateral coupling is also directly measured by applying a fast mechanical perturbation in the horizontal plane, thus ruling out changes in the contact geometry or molecular conformation as the source for the conductance change.
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Affiliation(s)
- Ismael Diez-Perez
- Center for Biosensors and Bioelectronics, Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA
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48
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Schmaus S, Bagrets A, Nahas Y, Yamada TK, Bork A, Bowen M, Beaurepaire E, Evers F, Wulfhekel W. Giant magnetoresistance through a single molecule. NATURE NANOTECHNOLOGY 2011; 6:185-9. [PMID: 21336269 DOI: 10.1038/nnano.2011.11] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Accepted: 01/14/2011] [Indexed: 05/17/2023]
Abstract
Magnetoresistance is a change in the resistance of a material system caused by an applied magnetic field. Giant magnetoresistance occurs in structures containing ferromagnetic contacts separated by a metallic non-magnetic spacer, and is now the basis of read heads for hard drives and for new forms of random access memory. Using an insulator (for example, a molecular thin film) rather than a metal as the spacer gives rise to tunnelling magnetoresistance, which typically produces a larger change in resistance for a given magnetic field strength, but also yields higher resistances, which are a disadvantage for real device operation. Here, we demonstrate giant magnetoresistance across a single, non-magnetic hydrogen phthalocyanine molecule contacted by the ferromagnetic tip of a scanning tunnelling microscope. We measure the magnetoresistance to be 60% and the conductance to be 0.26G(0), where G(0) is the quantum of conductance. Theoretical analysis identifies spin-dependent hybridization of molecular and electrode orbitals as the cause of the large magnetoresistance.
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Affiliation(s)
- Stefan Schmaus
- Physikalisches Institut, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany
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49
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Schull G, Frederiksen T, Arnau A, Sánchez-Portal D, Berndt R. Atomic-scale engineering of electrodes for single-molecule contacts. NATURE NANOTECHNOLOGY 2011; 6:23-7. [PMID: 21076405 DOI: 10.1038/nnano.2010.215] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2010] [Accepted: 10/07/2010] [Indexed: 05/22/2023]
Abstract
The transport of charge through a conducting material depends on the intrinsic ability of the material to conduct current and on the charge injection efficiency at the contacts between the conductor and the electrodes carrying current to and from the material. According to theoretical considerations, this concept remains valid down to the limit of single-molecule junctions. Exploring this limit in experiments requires atomic-scale control of the junction geometry. Here we present a method for probing the current through a single C(60) molecule while changing, one by one, the number of atoms in the electrode that are in contact with the molecule. We show quantitatively that the contact geometry has a strong influence on the conductance. We also find a crossover from a regime in which the conductance is limited by charge injection at the contact to a regime in which the conductance is limited by scattering at the molecule. Thus, the concepts of 'good' and 'bad' contacts, commonly used in macro- and mesoscopic physics, can also be applied at the molecular scale.
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Affiliation(s)
- Guillaume Schull
- Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504 (CNRS - Université de Strasbourg), 67034 Strasbourg, France.
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50
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Perera UGE, Kulik HJ, Iancu V, Dias da Silva LGGV, Ulloa SE, Marzari N, Hla SW. Spatially extended Kondo state in magnetic molecules induced by interfacial charge transfer. PHYSICAL REVIEW LETTERS 2010; 105:106601. [PMID: 20867535 DOI: 10.1103/physrevlett.105.106601] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2010] [Indexed: 05/29/2023]
Abstract
An extensive redistribution of spin density in TBrPP-Co molecules adsorbed on a Cu(111) surface is investigated by monitoring Kondo resonances at different locations on single molecules. Remarkably, the width of the Kondo resonance is found to be much larger on the organic ligands than on the central cobalt atom-reflecting enhanced spin-electron interactions on molecular orbitals. This unusual effect is explained by means of first-principles and numerical renormalization-group calculations highlighting the possibility to engineer spin polarization by exploiting interfacial charge transfer.
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Affiliation(s)
- U G E Perera
- Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701, USA
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