The statistical theory of quantum dots

Journal Article · Sun Oct 01 04:00:00 EDT 2000 · Reviews of Modern Physics

DOI:https://doi.org/10.1103/RevModPhys.72.895· OSTI ID:40206199

Alhassid, Y

A quantum dot is a sub-micron-scale conducting device containing up to several thousand electrons. Transport through a quantum dot at low temperatures is a quantum-coherent process. This review focuses on dots in which the electron's dynamics are chaotic or diffusive, giving rise to statistical properties that reflect the interplay between one-body chaos, quantum interference, and electron-electron interactions. The conductance through such dots displays mesoscopic fluctuations as a function of gate voltage, magnetic field, and shape deformation. The techniques used to describe these fluctuations include semiclassical methods, random-matrix theory, and the supersymmetric nonlinear {sigma} model. In open dots, the approximation of noninteracting quasiparticles is justified, and electron-electron interactions contribute indirectly through their effect on the dephasing time at finite temperature. In almost-closed dots, where conductance occurs by tunneling, the charge on the dot is quantized, and electron-electron interactions play an important role. Transport is dominated by Coulomb blockade, leading to peaks in the conductance that at low temperatures provide information on the dot's ground-state properties. Several statistical signatures of electron-electron interactions have been identified, most notably in the dot's addition spectrum. The dot's spin, determined partly by exchange interactions, can also influence the fluctuation properties of the conductance. Other mesoscopic phenomena in quantum dots that are affected by the charging energy include the fluctuations of the cotunneling conductance and mesoscopic Coulomb blockade.

• Sponsoring Organization: (US)
• OSTI ID: 40206199
• Journal Information: Reviews of Modern Physics, Journal Name: Reviews of Modern Physics Journal Issue: 4 Vol. 72; ISSN 0034-6861
• Publisher: The American Physical Society
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
DEFORMATION
ELECTRON-ELECTRON INTERACTIONS
ELECTRONS
EXCHANGE INTERACTIONS
FLUCTUATIONS
MAGNETIC FIELDS
SHAPE
SPIN
TRANSPORT
TUNNELING