A5048746133- Semiconductor materials and devices
- Quantum and electron transport phenomena
- Surface and Thin Film Phenomena
- Advancements in Semiconductor Devices and Circuit Design
- Electronic and Structural Properties of Oxides
- Force Microscopy Techniques and Applications
- Silicon and Solar Cell Technologies
- Molecular Junctions and Nanostructures
- Semiconductor Quantum Structures and Devices
- Advanced Materials Characterization Techniques
- Nanowire Synthesis and Applications
- Mechanical and Optical Resonators
- Quantum Information and Cryptography
- Thin-Film Transistor Technologies
- Physics of Superconductivity and Magnetism
- Photonic and Optical Devices
- Silicon Nanostructures and Photoluminescence
- Advancements in Photolithography Techniques
- Integrated Circuits and Semiconductor Failure Analysis
- Graphene research and applications
- Semiconductor materials and interfaces
- Electron and X-Ray Spectroscopy Techniques
- Surface Chemistry and Catalysis
- Advanced Surface Polishing Techniques
- Quantum optics and atomic interactions
National Institute of Standards and Technology
2014-2024
Physical Measurement Laboratory
2020-2024
National Institute of Standards
2015
The Hubbard model is an essential tool for understanding many-body physics in condensed matter systems. Artificial lattices of dopants silicon are a promising method the analog quantum simulation extended Fermi-Hubbard Hamiltonians strong interaction regime. However, complex atom-based device fabrication requirements have meant emulating tunable two-dimensional Hamiltonian has not been achieved. Here, we fabricate 3 × arrays single/few-dopant dots with finite disorder and demonstrate tuning...
Abstract Atomically precise fabrication has an important role to play in developing atom‐based electronic devices for use quantum information processing, materials research, and sensing. Atom‐by‐atom the potential enable control over tunnel coupling, exchange on‐site charging energies, other key properties of basic needed solid‐state computing analog simulation. Using hydrogen‐based scanning probe lithography, individual dopant atoms are deterministically placed relative atomically aligned...
Spin states in semiconductors provide exceptionally stable and noise-resistant environments for qubits, positioning them as optimal candidates reliable quantum computing technologies. The proposal to use nuclear electronic spins of donor atoms silicon, introduced by Kane 1998, sparked a new research field focused on the precise individual impurity devices, utilising scanning tunnelling microscopy ion implantation. This roadmap article reviews advancements 25 years since Kane's proposal,...
Abstract Spin states in semiconductors provide exceptionally stable and noise-resistant environments for qubits, positioning them as optimal candidates reliable quantum computing technologies. The proposal to use nuclear electronic spins of donor atoms silicon, introduced by Kane 1998, sparked a new research field focused on the precise individual impurity devices, utilising scanning tunnelling microscopy ion implantation. This roadmap article reviews advancements 25 years since Kane’s...
The doping of Si using the scanning probe hydrogen depassivation lithography technique has been shown to enable placing and positioning small numbers P atoms with nanometer accuracy. Several groups have now used this capability build devices that exhibit desired quantum behavior determined by their atomistic details. What remains elusive, however, is ability control precise number placed at a chosen site 100% yield, thereby limiting complexity degree perfection achievable. As an important...
Abstract Atomically precise donor-based quantum devices are a promising candidate for solid-state computing and analog simulations. However, critical challenges in atomically fabrication have meant systematic, atomic scale control of the tunneling rates tunnel coupling has not been demonstrated. Here using room temperature grown locking layer over entire process, we reduce unintentional dopant movement while achieving high quality epitaxy scanning tunnelling microscope (STM)-patterned...
The key building blocks for the fabrication of devices based on deterministic placement dopants in silicon using scanning tunneling microscopy (STM) hydrogen lithography are formation well-defined dopant delta-layers and overgrowth high quality crystalline Si. To develop these capabilities, it is critical importance to quantify movement sub-nanometer regime. this end, we investigate Si:P delta-layer samples produced by fully exposing a Si surface PH3 prior encapsulation with dramatically...
We develop an atomically precise fabrication and metrology strategy to control single dopant movement activation in Si:P monolayers.
Reducing the scale of etched nanostructures below 10 nm range eventually will require an atomic understanding masks being used in order to maintain exquisite control over both feature size and density. Here, authors demonstrate a method for tracking atomically resolved controlled structures from initial template definition through final nanostructure metrology, opening up pathway top–down nanofabrication. First, hydrogen depassivation lithography is performed on terminated Si(100) using...
Hydrogen atoms on a silicon surface, H–Si (100), behave as resist that can be patterned with perfect atomic precision using scanning tunneling microscope. When hydrogen atom is removed in this manner, the underlying presents chemically active site, commonly referred to dangling bond. It has been predicted individual bonds function artificial atoms, which, if grouped together, form designer molecules (100) surface. Here, we present an ring structure molecule spanning three dimer rows,...
Abstract Fabrication of quantum devices by atomic-scale patterning with scanning tunneling microscopy (STM) has led to the development single/few atom transistors, few-donor/quantum dot for spin manipulation, and arrayed few-donor analog simulation. We have developed atomic precision lithography, dopant incorporation, device encapsulation, ex situ re-location, contact processes enable high-yield fabrication. In this work, we describe a multiscale alignment strategy using Kelvin probe force...
Two-dimensional, $\ensuremath{\delta}$-doped Si:P structures are of interest for qubits, high-performance electronics, and quantum metamaterials. However, a lack low-resistance, high-yield Ohmic contacts to these subsurface, atomically thin systems has hampered applications. This study demonstrates Pd${}_{2}$Si with yield near 100%, which introduce only small parasitic resistance compatible the low-temperature processing needed an abrupt delta layer. technology enables reliable fabrication...
Single-layer steps at Si(100) surfaces/interfaces present significant challenges to the quantitative characterization of buried dopant devices as well accurate imaging and relocation fabricated quantum structures. We demonstrate detailed spatially resolved scanning tunneling spectroscopy study across monolayer step edges on surfaces determination local density state distributions behavior band gap edges. The influence electrostatic environment due edge states has been quantified while...
Reducing the scale of etched nanostructures below 10 nm range eventually will require an atomic understanding entire fabrication process being used in order to maintain exquisite control over both feature size and density. Here, we demonstrate a method for tracking atomically resolved controlled structures from initial template definition through final nanostructure metrology, opening up pathway top-down nanofabrication. Hydrogen depassivation lithography is first step nanoscale followed by...
The open-loop (OL) variant of Kelvin probe force microscopy (KPFM) provides access to the voltage response electrostatic interaction between a conductive atomic (AFM) and investigated sample. measured can be analyzed posteriori, modeled, interpreted include various contributions from geometry imaged features In contrast this, currently implemented closed-loop (CL) variants KPFM, either amplitude-modulation (AM) or frequency-modulation (FM), solely report on their final product in terms...
P+ monolayers in Si are of great scientific and technological interest, both intrinsically as a material the “ideal vacuum” crystalline because they showing promise qubits electron nuclear spin. The GHz complex conductivity σ(ω) can allow one to elucidate basic physical properties is also important for fast devices, but measuring 2D materials has not been easy. We report on such measurements, including (i) qualitatively lack any resonances up 5 (indicating no energy splittings below about...
We synthesized and studied color centers on silicon-on-insulator wafers with photoluminescence mapping spectroscopy, fabricated silicon W- G- center LEDs towards electrically-pumped single photon sources.
Coherent manipulation of electron spins is one the central challenges silicon-based quantum computing efforts. Electron spin resonance (ESR) lines, or Oersted allow 10–60 GHz radio frequency (RF) pulses to induce an electromagnetic field that drives Rabi oscillations in a dot interface. The these directly proportional strength induced field. We outline methodology for design printed circuit board and ESR line able transmit RF pulse 40 regime oscillating magnetic onto qubit device. propose...
The need for reliable quantum light sources drives our research to study color centers (CCs) in silicon as telecommunication O-band emitters. Building from photoluminescence measurements, we compare new electroluminescence measurements. To this end, synthesized CC-embedded p-i-n junctions silicon, creating CC light-emitting diode devices. two types of CCs were G-centers and W-centers, which show zero-phonon lines at approximately 1279 nm 1218 nm, respectively. Here, present device design,...
Abstract Color centers in silicon have recently gained considerable attention as single-photon sources and spin qubit-photon interfaces. However, one of the major bottlenecks to application color is their low overall brightness due a relatively slow emission rate poor light extraction from silicon. Here, we increase photon collection efficiency an ensemble particular kind center, known W centers, by embedding them circular Bragg grating cavities resonant with zero-phonon-line emission. We...
We fabricated circular Bragg grating cavities containing an ensemble of silicon color centers. For whose modes are resonant with the zero-phonon line emission centers, we observed a 5.5-fold enhancement in emitted intensity combined 1.3-fold increase decay rate.
The Hubbard model is one of the primary models for understanding essential many-body physics in condensed matter systems such as Mott insulators and cuprate high-Tc superconductors. Recent advances atomically precise fabrication silicon using scanning tunneling microscopy (STM) have made possible atom-by-atom single few-dopant quantum dots atomic-scale control dopant-based devices. However, complex requirements multi-component devices meant that emulating two-dimensional (2D) Fermi-Hubbard...