Eur. Phys. J. B 79, 351-356 (2011)
https://doi.org/10.1140/epjb/e2010-10603-1

Electronic properties of a quantum dot formed by the potentials associated with the surface acoustic wave and constrictions

¹ Laboratory of Mesoscopic and Low Dimensional Physics, College of Physical Science and Technology, Sichuan University, Chengdu, 610064, P.R. China
² National Institute of Measurement and Testing Technology, Chengdu, 610021, P.R. China

Corresponding author: ^a prof.j.gao@gmail.com

Received: 4 August 2010
Revised: 15 November 2010
Published online: 25 January 2011

Abstract

The electronic structure of dynamic quantum dots formed by surface acoustic waves potential and the confinement potential produced by gate voltage has been investigated within the spin-density-functional theory. We found the addition energy of this kind quantum dot in general decreases as the electron number increases, so the basic feature of the quantized acoustoelectric current with multi-plateaus can be reproduced. The addition energy needed for a second electron entering into the dynamic quantum dot is found to be about 2.21 meV, which is in good agreement with experimental estimations. Moreover, the formation of the Wigner molecule-like states is observed when the number of electrons in the dot exceeds three. By the calculated addition energy and the evolution of the electron density in the presence of a magnetic field, we also explained the influence of the magnetic field on the acoustoelectric current appeared in the experiments.