The Single-Atom Transistor: perspectives for quantum electronics on the atomic-scale

As silicon electronics approaches the atomic scale, interconnects and circuitry become comparable in size to the active device components. Maintaining low electrical resistivity at this scale is challenging because of the presence of conﬁning surfaces and interfaces. We report on the fabrication of wires in silicon—only one atom tall and four atoms wide—with exceptionally low resistivity (~0.3 milliohm-centimeters) and the current-carrying capabilities of copper. By embedding phosphorus atoms within a silicon crystal with an average spacing of less than 1 nanometer, we achieved a diameter-independent resistivity, which demonstrates ohmic scaling to the atomic limit. Atomistic tight-binding calculations conﬁrm the metallicity of these atomic-scale wires, which pave the way for single-atom device architectures for both classical and quantum information processing.

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Site-Specific Electrodeposition Enables Self-Terminating Growth of Atomically Dispersed Metal Catalysts

10.26434/chemrxiv.12287879.v1 ◽

2020 ◽

Author(s):

Yi Shi ◽

Wenmao Huang ◽

Jian Li ◽

Yue Zhou ◽

Zhongqiu Li ◽

...

Keyword(s):

Large Scale ◽

Transition Metal Dichalcogenides ◽

Metal Catalysts ◽

Atomic Scale ◽

Single Atom ◽

Scale Production ◽

Heterogenous Catalysis ◽

Site Specific ◽

Metal Support ◽

Metal Dichalcogenides

<p>The growth of atomically dispersed metal catalysts (ADMCs) remains a great challenge owing to the thermodynamically driven atom aggregation. Here we report a surface-limited electrodeposition technique that uses site-specific substrates for the rapid and room-temperature synthesis of ADMCs. We obtained ADMCs by the underpotential deposition (UPD) of a single-atom nonnoble metal onto the chalcogen atoms of chemically exfoliated transition metal dichalcogenides and subsequent galvanic displacement with a more-noble single-atom metal. The site-specific electrodeposition (SSED) enables the formation of energetically favorable metal–support bonds, and then automatically terminates the sequential formation of metallic bonding. The self-terminating effect restricts the metal deposition to the atomic scale. The modulated ADMCs exhibit remarkable activity and stability in the hydrogen evolution reaction compared to state-of-the-art single-atom electrocatalysts. We demonstrate that this SSED methodology could be extended to the synthesis of a variety of ADMCs (for example, Pt, Pd, Rh, Cu, Pb, Bi, and Sn single atoms), showing its general scope for the large-scale production of functional ADMCs in heterogenous catalysis. </p>

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Site-Specific Electrodeposition Enables Self-Terminating Growth of Atomically Dispersed Metal Catalysts

10.26434/chemrxiv.12287879 ◽

2020 ◽

Author(s):

Yi Shi ◽

Wenmao Huang ◽

Jian Li ◽

Yue Zhou ◽

Zhongqiu Li ◽

...

Keyword(s):

Large Scale ◽

Transition Metal Dichalcogenides ◽

Metal Catalysts ◽

Atomic Scale ◽

Single Atom ◽

Scale Production ◽

Heterogenous Catalysis ◽

Site Specific ◽

Metal Support ◽

Metal Dichalcogenides

<p>The growth of atomically dispersed metal catalysts (ADMCs) remains a great challenge owing to the thermodynamically driven atom aggregation. Here we report a surface-limited electrodeposition technique that uses site-specific substrates for the rapid and room-temperature synthesis of ADMCs. We obtained ADMCs by the underpotential deposition (UPD) of a single-atom nonnoble metal onto the chalcogen atoms of chemically exfoliated transition metal dichalcogenides and subsequent galvanic displacement with a more-noble single-atom metal. The site-specific electrodeposition (SSED) enables the formation of energetically favorable metal–support bonds, and then automatically terminates the sequential formation of metallic bonding. The self-terminating effect restricts the metal deposition to the atomic scale. The modulated ADMCs exhibit remarkable activity and stability in the hydrogen evolution reaction compared to state-of-the-art single-atom electrocatalysts. We demonstrate that this SSED methodology could be extended to the synthesis of a variety of ADMCs (for example, Pt, Pd, Rh, Cu, Pb, Bi, and Sn single atoms), showing its general scope for the large-scale production of functional ADMCs in heterogenous catalysis. </p>

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Single-atom vibrational spectroscopy in the scanning transmission electron microscope

Science ◽

10.1126/science.aba1136 ◽

2020 ◽

Vol 367 (6482) ◽

pp. 1124-1127 ◽

Cited By ~ 11

Author(s):

F. S. Hage ◽

G. Radtke ◽

D. M. Kepaptsoglou ◽

M. Lazzeri ◽

Q. M. Ramasse

Keyword(s):

Electron Microscope ◽

Vibrational Spectroscopy ◽

Materials Science ◽

Scanning Transmission Electron Microscope ◽

Atomic Scale ◽

Single Atom ◽

Phonon Modes ◽

Resonant States ◽

Resolution Electron ◽

Scanning Transmission

Single-atom impurities and other atomic-scale defects can notably alter the local vibrational responses of solids and, ultimately, their macroscopic properties. Using high-resolution electron energy-loss spectroscopy in the electron microscope, we show that a single substitutional silicon impurity in graphene induces a characteristic, localized modification of the vibrational response. Extensive ab initio calculations reveal that the measured spectroscopic signature arises from defect-induced pseudo-localized phonon modes—that is, resonant states resulting from the hybridization of the defect modes and the bulk continuum—with energies that can be directly matched to the experiments. This finding realizes the promise of vibrational spectroscopy in the electron microscope with single-atom sensitivity and has broad implications across the fields of physics, chemistry, and materials science.

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Quantitative Annular Dark Field Electron Microscopy Using Single Electron Signals

Microscopy and Microanalysis ◽

10.1017/s1431927613013664 ◽

2013 ◽

Vol 20 (1) ◽

pp. 99-110 ◽

Cited By ~ 50

Author(s):

Ryo Ishikawa ◽

Andrew R. Lupini ◽

Scott D. Findlay ◽

Stephen J. Pennycook

Keyword(s):

Electron Microscopy ◽

Dynamic Range ◽

Light Element ◽

Dark Field ◽

Atomic Scale ◽

Single Electron ◽

Single Atom ◽

Intensity Level ◽

Primitive Cell ◽

Annular Dark Field

AbstractOne of the difficulties in analyzing atomic resolution electron microscope images is that the sample thickness is usually unknown or has to be fitted from parameters that are not precisely known. An accurate measure of thickness, ideally on a column-by-column basis, parameter free, and with single atom accuracy, would be of great value for many applications, such as matching to simulations. Here we propose such a quantification method for annular dark field scanning transmission electron microscopy by using the single electron intensity level of the detector. This method has the advantage that we can routinely quantify annular dark field images operating at both low and high beam currents, and under high dynamic range conditions, which is useful for the quantification of ultra-thin or light-element materials. To facilitate atom counting at the atomic scale we use the mean intensity in an annular dark field image averaged over a primitive cell, with no free parameters to be fitted. To illustrate the potential of our method, we demonstrate counting the number of Al (or N) atoms in a wurtzite-type aluminum nitride single crystal at each primitive cell over the range of 3–99 atoms.

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Site-specific electrodeposition enables self-terminating growth of atomically dispersed metal catalysts

Nature Communications ◽

10.1038/s41467-020-18430-8 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Yi Shi ◽

Wen-Mao Huang ◽

Jian Li ◽

Yue Zhou ◽

Zhong-Qiu Li ◽

...

Keyword(s):

Transition Metal Dichalcogenides ◽

Metal Catalysts ◽

Atomic Scale ◽

Single Atom ◽

Site Specific ◽

Metal Support ◽

Metal Dichalcogenides ◽

Metallic Bonding ◽

General Scope ◽

Sequential Formation

Abstract The growth of atomically dispersed metal catalysts (ADMCs) remains a great challenge owing to the thermodynamically driven atom aggregation. Here we report a surface-limited electrodeposition technique that uses site-specific substrates for the rapid and room-temperature synthesis of ADMCs. We obtained ADMCs by the underpotential deposition of a non-noble single-atom metal onto the chalcogen atoms of transition metal dichalcogenides and subsequent galvanic displacement with a more-noble single-atom metal. The site-specific electrodeposition enables the formation of energetically favorable metal–support bonds, and then automatically terminates the sequential formation of metallic bonding. The self-terminating effect restricts the metal deposition to the atomic scale. The modulated ADMCs exhibit remarkable activity and stability in the hydrogen evolution reaction compared to state-of-the-art single-atom electrocatalysts. We demonstrate that this methodology could be extended to the synthesis of a variety of ADMCs (Pt, Pd, Rh, Cu, Pb, Bi, and Sn), showing its general scope for functional ADMCs manufacturing in heterogeneous catalysis.

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Magnetic-Field Probing of an SU(4) Kondo Resonance in a Single-Atom Transistor

Physical Review Letters ◽

10.1103/physrevlett.108.046803 ◽

2012 ◽

Vol 108 (4) ◽

Cited By ~ 49

Author(s):

G. C. Tettamanzi ◽

J. Verduijn ◽

G. P. Lansbergen ◽

M. Blaauboer ◽

M. J. Calderón ◽

...

Keyword(s):

Magnetic Field ◽

Single Atom ◽

Kondo Resonance ◽

Atom Transistor

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Multi-step atomic mechanism of platinum nanocrystals nucleation and growth revealed by in-situ liquid cell STEM

Scientific Reports ◽

10.1038/s41598-021-03455-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Walid Dachraoui ◽

Trond R. Henninen ◽

Debora Keller ◽

Rolf Erni

Keyword(s):

Liquid Phase ◽

Driving Forces ◽

Classical Model ◽

Theoretical Models ◽

Atomic Scale ◽

Single Atom ◽

Growth Mechanisms ◽

Platinum Nanocrystals ◽

Scanning Transmission

AbstractThe understanding of crystal growth mechanisms has broadened substantially. One significant advancement is based in the conception that the interaction between particles plays an important role in the growth of nanomaterials. This is in contrast to the classical model, which neglects this process. Direct imaging of such processes at atomic-level in liquid-phase is essential for establishing new theoretical models that encompass the full complexity of realistic scenarios and eventually allow for tailoring nanoparticle growth. Here, we investigate at atomic-scale the exact growth mechanisms of platinum nanocrystals from single atom to final crystals by in-situ liquid phase scanning transmission electron microscopy. We show that, after nucleation, the nanocrystals grow via two main stages: atomic attachment in the first stage, where the particles initially grow by attachment of the atoms until depletion of the surrounding zone. Thereafter, follows the second stage of growth, which is based on particle attachment by different atomic pathways to finally form mature nanoparticles. The atomic mechanisms underlying these growth pathways are distinctly different and have different driving forces and kinetics as evidenced by our experimental observations.

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Hyperfine interaction of individual atoms on a surface

Science ◽

10.1126/science.aat7047 ◽

2018 ◽

Vol 362 (6412) ◽

pp. 336-339 ◽

Cited By ~ 21

Author(s):

Philip Willke ◽

Yujeong Bae ◽

Kai Yang ◽

Jose L. Lado ◽

Alejandro Ferrón ◽

...

Keyword(s):

Hyperfine Interaction ◽

Atomic Scale ◽

Single Atom ◽

Scanning Tunneling ◽

Oxide Surface ◽

Nuclear Spins ◽

Tunneling Microscopy ◽

Magnesium Oxide Surface ◽

State Mixing ◽

And Control

Taking advantage of nuclear spins for electronic structure analysis, magnetic resonance imaging, and quantum devices hinges on knowledge and control of the surrounding atomic-scale environment. We measured and manipulated the hyperfine interaction of individual iron and titanium atoms placed on a magnesium oxide surface by using spin-polarized scanning tunneling microscopy in combination with single-atom electron spin resonance. Using atom manipulation to move single atoms, we found that the hyperfine interaction strongly depended on the binding configuration of the atom. We could extract atom- and position-dependent information about the electronic ground state, the state mixing with neighboring atoms, and properties of the nuclear spin. Thus, the hyperfine spectrum becomes a powerful probe of the chemical environment of individual atoms and nanostructures.

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