Magnetic field and dissipation effects on the charge polarization in quantum cellular automata

Author

Rojas, Fernando ; Cota, Ernesto ; Ulloa, Sergio E.

Author_Institution

Dept. of Theor. Phys., Univ. Nacional Autonoma de Mexico, Baja California, Mexico

Volume

3

Issue

1

fYear

2004

fDate

3/1/2004 12:00:00 AM

Firstpage

37

Lastpage

41

Abstract

We study the dynamic evolution of the charge distribution (polarization) of a 2×2 quantum-dot cell with two electrons in the presence of a time-dependent driver cell and a magnetic field. We describe the effects of the magnetic flux on the response of the basic dot cell, for fixed, and linear switching of the driver polarization. In the static case, we find that the magnetic field has a strong localizing effect, similar to the effect of asymmetry. For fixed tunneling, the polarization of the target cell increases with magnetic field, going through a maximum at a particular value of the magnetic flux through the cell. In the dynamic case, a ringing effect and a decrease in the final polarization value of the target cell are obtained as the magnetic field increases. The effects of temperature and asymmetry on these results are also analyzed.

Keywords

Hubbard model; cellular automata; localised states; magnetic field effects; quantum dots; tunnelling; charge distribution; charge polarization; dissipation effects; driver polarization; linear switching; localizing effect; magnetic field effects; quantum cellular automata; quantum dot cell; ringing effect; tunneling; Electrons; Magnetic analysis; Magnetic fields; Magnetic flux; Magnetic switching; Magnetic tunneling; Polarization; Quantum cellular automata; Quantum dots; Temperature;

fLanguage

English

Journal_Title

Nanotechnology, IEEE Transactions on

Publisher

ieee

ISSN

1536-125X

Type

jour

DOI

10.1109/TNANO.2004.824009

Filename

1278266