Electrons in artificial atoms

  title={Electrons in artificial atoms},
  author={Raymond C. Ashoori},
  • R. Ashoori
  • Published 1 February 1996
  • Chemistry
  • Nature
Progress in semiconductor technology has enabled the fabrication of structures so small that they can contain just one mobile electron. By varying controllably the number of electrons in these 'artificial atoms' and measuring the energy required to add successive electrons, one can conduct atomic physics experiments in a regime that is inaccessible to experiments on real atoms. 
Artificial atoms based on correlated materials.
An overview of the fundamental properties of low-dimensional electron systems fabricated from quantum matter is given and the concept of artificial atoms fabricated from Quantum materials is considered, anticipating remarkable scientific advances and possibly important applications of this new field of research.
The single electron transistor and artificial atoms
Modern techniques of lithography make it possible to confine electrons to sufficiently small dimensions that the quantization of both their charge and their energy are easily observable. When such
Kondo physics with single electron transistors
The coupling between the confined droplet of electrons and the leads in a single electron transistor (SET) has made it possible to explore Kondo physics in ways that were never before possible. In
Artificial Atoms: New Boxes for Electrons
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Electron correlation in artificial atoms
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Quantum-dot molecules were constructed on a semiconductor surface using atom manipulation by scanning tunneling microscopy by exploiting tunnel barriers created reversibly using the STM tip to create a series of reconfigurable quantum- dot molecules with atomic precision.
Formation of Wigner molecules in small quantum dots
It was recently argued that in small quantum dots the electrons could crystallize at much higher densities than in the infinite two-dimensional electron gas. We compare predictions that the onset of
Collective Properties of Electrons and Holes in Coupled Quantum Dots
We discuss the properties of few electrons and electron-hole pairs confined in coupled semiconductor quantum dots, with emphasis on correlation effects and the role of tunneling. We discuss, in
Interacting electrons in artificial molecules with magnetic field of arbitrary direction
Abstract We theoretically investigate the mechanisms for the magnetic field-induced singlet–triplet transition of two electrons in vertically coupled quantum dots, as a function of the field strength


Single-electron charging of quantum-dot atoms.
Arrays of field-effect-confined quantum dots with diameters smaller than 100 nm have been prepared and discrete steps in the gate-voltage dependence of the integrated absorption strength are observed indicating directly the incremental occupation of each dot with N=1, 2, 3, and 4 electrons.
Single-electron capacitance spectroscopy of few-electron artificial atoms in a magnetic field: Theory and experiment.
  • Hawrylak
  • Materials Science, Medicine
    Physical review letters
  • 1993
The evidence for magnetic field induced spin and angular momentum transitions in the strongly interacting artificial atom is presented.
Exchange Effects in an Artificial Atom at High Magnetic Fields.
In the spin polarized regime, a new phase is observed also predicted by Hartree-Fock theory, where a divergent spin susceptibility at B is suggested, implying a ground state of minimum total spin just below B.
Transport spectroscopy of a confined electron system under a gate tip.
Conductance resonances measured for split-gate structures around threshold are interpreted in terms of single-electron tunneling through a quantum dot beneath the tip of the gate finger, consistent with a minimal number of seven electrons in the quantum dot.
Single-electron capacitance spectroscopy of discrete quantum levels.
The capacitance signal resulting from single electrons tunneling into discrete quantum levels is observed and the nature of the bound states is deduced from the magnetic field evolution of the spectrum.
Fabrication technique for Si single-electron transistor operating at room temperature
A Si single electron transistor (SET) was fabricated by converting a one-dimensional Si wire on a SIMOX substrate into a small Si island with a tunnelling barrier at each end by means of
Quantum dots in a magnetic field: Role of electron-electron interactions.
The eigenstates of electrons interacting in quantum dots in a magnetic field are studied and their effects on the magnetic-field dependence of the energy spectrum are illustrated with the calculations of the electronic heat capacity.
Single-electron charging and periodic conductance resonances in GaAs nanostructures.
Narrow channels interrupted by two controlled potential barriers and having a tunable electron density were made in GaAs, and their conductance was measured at low temperatures. Reproducible and
Competing channels in single-electron tunneling through a quantum dot.
It is shown that transport occurring via transitions between ground states with different numbers of electrons can be suppressed by the occupation of excited states.
Correlated few-electron states in vertical double-quantum-dot systems.
The combined effect of a high magnetic field, electrostatic confinement, and inter-dot coupling, induces a new class of few-electron ground states absent in single quantum dots.