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Pitters J, Croshaw J, Achal R, Livadaru L, Ng S, Lupoiu R, Chutora T, Huff T, Walus K, Wolkow RA. Atomically Precise Manufacturing of Silicon Electronics. ACS NANO 2024; 18:6766-6816. [PMID: 38376086 PMCID: PMC10919096 DOI: 10.1021/acsnano.3c10412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 02/01/2024] [Accepted: 02/06/2024] [Indexed: 02/21/2024]
Abstract
Atomically precise manufacturing (APM) is a key technique that involves the direct control of atoms in order to manufacture products or components of products. It has been developed most successfully using scanning probe methods and has received particular attention for developing atom scale electronics with a focus on silicon-based systems. This review captures the development of silicon atom-based electronics and is divided into several sections that will cover characterization and atom manipulation of silicon surfaces with scanning tunneling microscopy and atomic force microscopy, development of silicon dangling bonds as atomic quantum dots, creation of atom scale devices, and the wiring and packaging of those circuits. The review will also cover the advance of silicon dangling bond logic design and the progress of silicon quantum atomic designer (SiQAD) simulators. Finally, an outlook of APM and silicon atom electronics will be provided.
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Affiliation(s)
- Jason Pitters
- Nanotechnology
Research Centre, National Research Council
of Canada, Edmonton, Alberta T6G 2M9, Canada
| | - Jeremiah Croshaw
- Department
of Physics, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Roshan Achal
- Department
of Physics, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
- Quantum
Silicon Inc., Edmonton, Alberta T6G 2M9, Canada
| | - Lucian Livadaru
- Department
of Physics, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
- Quantum
Silicon Inc., Edmonton, Alberta T6G 2M9, Canada
| | - Samuel Ng
- Department
of Electrical and Computer Engineering, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Robert Lupoiu
- School
of Engineering, Stanford University, Stanford, California 94305, United States
| | - Taras Chutora
- Department
of Physics, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Taleana Huff
- Canadian
Bank Note Company, Ottawa, Ontario K1Z 1A1, Canada
| | - Konrad Walus
- Department
of Electrical and Computer Engineering, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Robert A. Wolkow
- Department
of Physics, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
- Quantum
Silicon Inc., Edmonton, Alberta T6G 2M9, Canada
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2
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Ultra-shallow dopant profiles as in-situ electrodes in scanning probe microscopy. Sci Rep 2022; 12:3783. [PMID: 35260623 PMCID: PMC8904578 DOI: 10.1038/s41598-022-07551-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 02/21/2022] [Indexed: 11/25/2022] Open
Abstract
The application of nano materials to control advanced functionality in semiconductor devices has reached the atomic scale. At this dimension the exact chemical and structural composition of a device is crucial for its performance. Rapid inspection techniques are required to find the optimal combination among numerous materials. However, to date the earliest electrical inspection is carried out after multiple fabrication processes. This delay makes the fabrication of atomically designed components very challenging. Here, we propose a sample system to chemically characterize nanoscale devices in-operando. We introduce ion-implanted contacts which embedded in the sample serve as additional electrodes to carry out scanning gate experiments. We demonstrate that the presence of these electrodes does not deteriorate the surface quality. The potential of this approach is highlighted by controlling the charge state of single dangling bonds on the silicon surface. Apart from our novel sample holder, the experimental setup was not modified making this approach compatible to most commercial low-temperature scanning probe microscopes. For silicon based devices, the versatility of this method is a promising avenue to gain a detailed and rapid understanding of functionalized atomic devices and quantum interactions at the atomic level.
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3
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Onoda J, Khademi A, Wolkow RA, Pitters J. Ohmic Contact to Two-Dimensional Nanofabricated Silicon Structures with a Two-Probe Scanning Tunneling Microscope. ACS NANO 2021; 15:19377-19386. [PMID: 34780687 DOI: 10.1021/acsnano.1c05777] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
We used multiprobe scanning tunneling microscope (STM) to fabricate and electrically characterize nanostructures on Si surfaces. We overcame resistive contacts by using field evaporation to clean tip apexes in order to create Ohmic contact with the Si surface states on a Si substrate. A two-probe (2P-) STM with Ohmic contact allowed for measurement at very low bias, limiting conduction through space-charge layer and bulk states. The Ohmic 2P-STM measurement clarified the surface conductivity of the Si(111)-(7 × 7) surface. We also confirmed that Ohmic 2P-STM can be replaced with more convenient Ohmic one-probe STM for the conductance measurements on the Si surface. We prepared nanostructures using STM lithography to define electronically isolated two-dimensional (2D) regions with various aspect ratios. Their surface conduction properties are described well by the conventional sheet model, proving the diffusive 2D conduction on the Si surface. Constrictions and breaks in 2D structures were also evaluated. Ohmic 2P-STM will be helpful for the investigation of exploratory atomic-scale circuitry or cutting-edge materials sciences.
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Affiliation(s)
- Jo Onoda
- Department of Physics, University of Alberta, Edmonton, Alberta T6G 2J1, Canada
| | - Ali Khademi
- Metrology Research Centre, National Research Council of Canada, 1200 Montreal Road, Ottawa, Ontario K1A 0R6, Canada
| | - Robert A Wolkow
- Department of Physics, University of Alberta, Edmonton, Alberta T6G 2J1, Canada
- Quantum Silicon, Inc., Edmonton Alberta T6G 2M9, Canada
| | - Jason Pitters
- Nanotechnology Research Centre, National Research Council Canada, Edmonton, Alberta T6G 2M9, Canada
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4
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Civita D, Kolmer M, Simpson GJ, Li AP, Hecht S, Grill L. Control of long-distance motion of single molecules on a surface. Science 2020; 370:957-960. [PMID: 33214276 DOI: 10.1126/science.abd0696] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 08/27/2020] [Indexed: 11/02/2022]
Abstract
Spatial control over molecular movement is typically limited because motion at the atomic scale follows stochastic processes. We used scanning tunneling microscopy to bring single molecules into a stable orientation of high translational mobility where they moved along precisely defined tracks. Single dibromoterfluorene molecules moved over large distances of 150 nanometers with extremely high spatial precision of 0.1 angstrom across a silver (111) surface. The electrostatic nature of the effect enabled the selective application of repulsive and attractive forces to send or receive single molecules. The high control allows us to precisely move an individual and specific molecular entity between two separate probes, opening avenues for velocity measurements and thus energy dissipation studies of single molecules in real time during diffusion and collision.
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Affiliation(s)
- Donato Civita
- Department of Physical Chemistry, University of Graz, Heinrichstrasse 28, 8010 Graz, Austria
| | - Marek Kolmer
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Grant J Simpson
- Department of Physical Chemistry, University of Graz, Heinrichstrasse 28, 8010 Graz, Austria
| | - An-Ping Li
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Stefan Hecht
- Department of Chemistry and IRIS Adlershof, Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489 Berlin, Germany.,DWI -Leibniz Institute for Interactive Materials, Forckenbeckstr. 50, 52074 Aachen, Germany.,Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringer Weg 2, 52074 Aachen, Germany
| | - Leonhard Grill
- Department of Physical Chemistry, University of Graz, Heinrichstrasse 28, 8010 Graz, Austria.
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5
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Leeuwenhoek M, Groenewoud F, van Oosten K, Benschop T, Allan MP, Gröblacher S. Fabrication of on-chip probes for double-tip scanning tunneling microscopy. MICROSYSTEMS & NANOENGINEERING 2020; 6:99. [PMID: 34567708 PMCID: PMC8433193 DOI: 10.1038/s41378-020-00209-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 08/28/2020] [Accepted: 09/01/2020] [Indexed: 05/22/2023]
Abstract
A reduction of the interprobe distance in multiprobe and double-tip scanning tunneling microscopy to the nanometer scale has been a longstanding and technically difficult challenge. Recent multiprobe systems have allowed for significant progress by achieving distances of ~30 nm using two individually driven, traditional metal wire tips. For situations where simple alignment and fixed separation can be advantageous, we present the fabrication of on-chip double-tip devices that incorporate two mechanically fixed gold tips with a tip separation of only 35 nm. We utilize the excellent mechanical, insulating and dielectric properties of high-quality SiN as a base material to realize easy-to-implement, lithographically defined and mechanically stable tips. With their large contact pads and adjustable footprint, these novel tips can be easily integrated with most existing commercial combined STM/AFM systems.
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Affiliation(s)
- Maarten Leeuwenhoek
- Kavli Institute of Nanoscience, Department of Quantum Nanoscience, Delft University of Technology, Lorentzweg 1, 2628CJ Delft, The Netherlands
- Leiden Institute of Physics, Leiden University, Niels Bohrweg 2, 2333CA Leiden, The Netherlands
| | - Freek Groenewoud
- Leiden Institute of Physics, Leiden University, Niels Bohrweg 2, 2333CA Leiden, The Netherlands
| | - Kees van Oosten
- Leiden Institute of Physics, Leiden University, Niels Bohrweg 2, 2333CA Leiden, The Netherlands
| | - Tjerk Benschop
- Leiden Institute of Physics, Leiden University, Niels Bohrweg 2, 2333CA Leiden, The Netherlands
| | - Milan P. Allan
- Leiden Institute of Physics, Leiden University, Niels Bohrweg 2, 2333CA Leiden, The Netherlands
| | - Simon Gröblacher
- Kavli Institute of Nanoscience, Department of Quantum Nanoscience, Delft University of Technology, Lorentzweg 1, 2628CJ Delft, The Netherlands
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Leeuwenhoek M, Norte RA, Bastiaans KM, Cho D, Battisti I, Blanter YM, Gröblacher S, Allan MP. Nanofabricated tips for device-based scanning tunneling microscopy. NANOTECHNOLOGY 2019; 30:335702. [PMID: 31022709 DOI: 10.1088/1361-6528/ab1c7f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
We report on the fabrication and performance of a new kind of tip for scanning tunneling microscopy. By fully incorporating a metallic tip on a silicon chip using modern micromachining and nanofabrication techniques, we realize so-called smart tips and show the possibility of device-based STM tips. Contrary to conventional etched metal wire tips, these can be integrated into lithographically defined electrical circuits. We describe a new fabrication method to create a defined apex on a silicon chip and experimentally demonstrate the high performance of the smart tips, both in stability and resolution. In situ tip preparation methods are possible and we verify that they can resolve the herringbone reconstruction and Friedel oscillations on Au(111) surfaces. We further present an overview of possible applications.
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Affiliation(s)
- Maarten Leeuwenhoek
- Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628CJ Delft, The Netherlands. Leiden Institute of Physics, Leiden University, Niels Bohrweg 2, 2333CA Leiden, The Netherlands
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7
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Calogero G, Alcón I, Papior N, Jauho AP, Brandbyge M. Quantum Interference Engineering of Nanoporous Graphene for Carbon Nanocircuitry. J Am Chem Soc 2019; 141:13081-13088. [DOI: 10.1021/jacs.9b04649] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Gaetano Calogero
- Center for Nanostructured Graphene (CNG), DK-2800 Kongens Lyngby, Denmark
| | - Isaac Alcón
- Center for Nanostructured Graphene (CNG), DK-2800 Kongens Lyngby, Denmark
| | - Nick Papior
- Center for Nanostructured Graphene (CNG), DK-2800 Kongens Lyngby, Denmark
| | - Antti-Pekka Jauho
- Center for Nanostructured Graphene (CNG), DK-2800 Kongens Lyngby, Denmark
| | - Mads Brandbyge
- Center for Nanostructured Graphene (CNG), DK-2800 Kongens Lyngby, Denmark
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8
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Electronic transport in planar atomic-scale structures measured by two-probe scanning tunneling spectroscopy. Nat Commun 2019; 10:1573. [PMID: 30952953 PMCID: PMC6450957 DOI: 10.1038/s41467-019-09315-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 02/27/2019] [Indexed: 11/09/2022] Open
Abstract
Miniaturization of electronic circuits into the single-atom level requires novel approaches to characterize transport properties. Due to its unrivaled precision, scanning probe microscopy is regarded as the method of choice for local characterization of atoms and single molecules supported on surfaces. Here we investigate electronic transport along the anisotropic germanium (001) surface with the use of two-probe scanning tunneling spectroscopy and first-principles transport calculations. We introduce a method for the determination of the transconductance in our two-probe experimental setup and demonstrate how it captures energy-resolved information about electronic transport through the unoccupied surface states. The sequential opening of two transport channels within the quasi-one-dimensional Ge dimer rows in the surface gives rise to two distinct resonances in the transconductance spectroscopic signal, consistent with phase-coherence lengths of up to 50 nm and anisotropic electron propagation. Our work paves the way for the electronic transport characterization of quantum circuits engineered on surfaces. Measuring electronic transport at the atomic scale requires atom precise contacts. Here, the authors demonstrate quasi-one-dimensional electronic transport along a single dimer row on a germanium surface using a two probe scanning tunneling microscopy protocol.
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9
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Calogero G, Papior NR, Kretz B, Garcia-Lekue A, Frederiksen T, Brandbyge M. Electron Transport in Nanoporous Graphene: Probing the Talbot Effect. NANO LETTERS 2019; 19:576-581. [PMID: 30539639 DOI: 10.1021/acs.nanolett.8b04616] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Electrons in graphene can show diffraction and interference phenomena fully analogous to light thanks to their Dirac-like energy dispersion. However, it is not clear how this optical analogy persists in nanostructured graphene, for example, with pores. Nanoporous graphene (NPG) consisting of linked graphene nanoribbons has recently been fabricated using molecular precursors and bottom-up assembly (Moreno et al. Science 2018, 360, 199). We predict that electrons propagating in NPG exhibit the interference Talbot effect, analogous to photons in coupled waveguides. Our results are obtained by parameter-free atomistic calculations of real-sized NPG samples based on seamlessly integrated density functional theory and tight-binding regions. We link the origins of this interference phenomenon to the band structure of the NPG. Most importantly, we demonstrate how the Talbot effect may be detected experimentally using dual-probe scanning tunneling microscopy. Talbot interference of electron waves in NPG or other related materials may open up new opportunities for future quantum electronics, computing, or sensing.
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Affiliation(s)
- Gaetano Calogero
- Department of Micro- and Nanotechnology, Center for Nanostructured Graphene (CNG) , Technical University of Denmark , DK-2800 Kongens Lyngby , Denmark
| | - Nick R Papior
- Department of Micro- and Nanotechnology, Center for Nanostructured Graphene (CNG) , Technical University of Denmark , DK-2800 Kongens Lyngby , Denmark
| | - Bernhard Kretz
- Institute of Theoretical Physics , University of Regensburg , 93040 Regensburg , Germany
| | - Aran Garcia-Lekue
- Donostia International Physics Center (DIPC) , 20018 San Sebastian , Spain
- Ikerbasque, Basque Foundation for Science , 48013 Bilbao , Spain
| | - Thomas Frederiksen
- Donostia International Physics Center (DIPC) , 20018 San Sebastian , Spain
- Ikerbasque, Basque Foundation for Science , 48013 Bilbao , Spain
| | - Mads Brandbyge
- Department of Micro- and Nanotechnology, Center for Nanostructured Graphene (CNG) , Technical University of Denmark , DK-2800 Kongens Lyngby , Denmark
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10
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Voigtländer B, Tegenkamp C. Special issue on multiprobe techniques. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2018; 30:490301. [PMID: 30457111 DOI: 10.1088/1361-648x/aaee03] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
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11
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Voigtländer B, Cherepanov V, Korte S, Leis A, Cuma D, Just S, Lüpke F. Invited Review Article: Multi-tip scanning tunneling microscopy: Experimental techniques and data analysis. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:101101. [PMID: 30399776 DOI: 10.1063/1.5042346] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 08/25/2018] [Indexed: 06/08/2023]
Abstract
In scanning tunneling microscopy, we witness in recent years a paradigm shift from "just imaging" to detailed spectroscopic measurements at the nanoscale and multi-tip scanning tunneling microscope (STM) is a technique following this trend. It is capable of performing nanoscale charge transport measurements like a "multimeter at the nanoscale." Distance-dependent four-point measurements, the acquisition of nanoscale potential maps at current carrying nanostructures and surfaces, as well as the acquisition of I - V curves of nanoelectronic devices are examples of the capabilities of the multi-tip STM technique. In this review, we focus on two aspects: How to perform the multi-tip STM measurements and how to analyze the acquired data in order to gain insight into nanoscale charge transport processes for a variety of samples. We further discuss specifics of the electronics for multi-tip STM and the properties of tips for multi-tip STM, and present methods for a tip approach to nanostructures on insulating substrates. We introduce methods on how to extract the conductivity/resistivity for mixed 2D/3D systems from four-point measurements, how to measure the conductivity of 2D sheets, and how to introduce scanning tunneling potentiometry measurements with a multi-tip setup. For the example of multi-tip measurements at freestanding vapor liquid solid grown nanowires, we discuss contact resistances as well as the influence of the presence of the probing tips on the four point measurements.
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Affiliation(s)
- Bert Voigtländer
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich and JARA-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Vasily Cherepanov
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich and JARA-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Stefan Korte
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich and JARA-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Arthur Leis
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich and JARA-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - David Cuma
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich and JARA-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Sven Just
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich and JARA-Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - Felix Lüpke
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich and JARA-Fundamentals of Future Information Technology, 52425 Jülich, Germany
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12
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Shaterzadeh-Yazdi Z, Sanders BC, DiLabio GA. Ab initio characterization of coupling strength for all types of dangling-bond pairs on the hydrogen-terminated Si(100)-2 × 1 surface. J Chem Phys 2018; 148:154701. [PMID: 29679977 DOI: 10.1063/1.5020873] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Recent work has suggested that coupled silicon dangling bonds sharing an excess electron may serve as building blocks for quantum-cellular-automata cells and quantum computing schemes when constructed on hydrogen-terminated silicon surfaces. In this work, we employ ab initio density-functional theory to examine the details associated with the coupling between two dangling bonds sharing one excess electron and arranged in various configurations on models of phosphorous-doped hydrogen-terminated silicon (100) surfaces. Our results show that the coupling strength depends strongly on the relative orientation of the dangling bonds on the surface and on the separation between them. The orientation of dangling bonds is determined by the anisotropy of the silicon (100) surface, so this feature of the surface is a significant contributing factor to variations in the strength of coupling between dangling bonds. The results demonstrate that simple models for approximating tunneling, such as the Wentzel-Kramer-Brillouin method, which do not incorporate the details of surface structure, are incapable of providing reasonable estimates of tunneling rates between dangling bonds. The results provide guidance to efforts related to the development of dangling-bond based computing elements.
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Affiliation(s)
- Zahra Shaterzadeh-Yazdi
- School of Engineering Science, College of Engineering, University of Tehran, 16th Azar Street, Enghelab Square, Tehran, Iran
| | - Barry C Sanders
- Institute for Quantum Science and Technology, University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - Gino A DiLabio
- Department of Chemistry, University of British Columbia, 3247 University Way, Kelowna, British Columbia V1V 1V7, Canada
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13
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Leisegang M, Kügel J, Klein L, Bode M. Analyzing the Wave Nature of Hot Electrons with a Molecular Nanoprobe. NANO LETTERS 2018; 18:2165-2171. [PMID: 29486560 DOI: 10.1021/acs.nanolett.8b00465] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We report on a novel method, the molecular nanoprobe (MONA) technique, which allows us to measure the nanoscale quasiparticle transport between two arbitrary surface points. In these experiments, hot electrons are injected into the sample surface from the probe tip of a scanning tunneling microscope (STM) and detected by tautomerization switching events of a single deprotonated phthalocyanine (H2Pc) molecule. By making use of atom-by-atom-engineered interferometers on a Ag(111) surface, we demonstrate that the quantum-mechanical wave nature of hot electrons leads to characteristic oscillations of the molecule tautomerization probability. Two interferometers can be combined to build an energy-dependent selector, which allows it to selectively switch one out of two molecules without changing the position of the STM tip. The MONA technique is compared with conventional d I/d U measurements, where the injection and detection point of hot electrons is intrinsically tied to the same tip location.
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Affiliation(s)
- Markus Leisegang
- Physikalisches Institut, Experimentelle Physik II , Universität Würzburg , Am Hubland , 97074 Würzburg , Germany
| | - Jens Kügel
- Physikalisches Institut, Experimentelle Physik II , Universität Würzburg , Am Hubland , 97074 Würzburg , Germany
| | - Lucas Klein
- Physikalisches Institut, Experimentelle Physik II , Universität Würzburg , Am Hubland , 97074 Würzburg , Germany
| | - Matthias Bode
- Physikalisches Institut, Experimentelle Physik II , Universität Würzburg , Am Hubland , 97074 Würzburg , Germany
- Wilhelm Conrad Röntgen-Center for Complex Material Systems (RCCM) , Universität Würzburg , Am Hubland , D-97074 Würzburg , Germany
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