Singlet-triplet splitting, correlation and entanglement of two electrons in quantum dot molecules

Details Singlet-triplet splitting, correlation and entanglement of two electrons in quantum dot molecules Singlet-triplet splitting, correlation and entanglement of two electrons in quantum dot molecules

2005-03-19

arxiv.org/abs/cond-mat/0503492v4

Phys. Rev. B 72, 195307 (2005)

Physics

Condensed Matter

Materials Science

13 pages, 9 figures. To appear in Phys. Rev. B

Scientific paper

10.1103/PhysRevB.72.195307

Starting with an accurate pseudopotential description of the single-particle states, and following by configuration-interaction treatment of correlated electrons in vertically coupled, self-assembled InAs/GaAs quantum dot-molecules, we show how simpler, popularly-practiced approximations, depict the basic physical characteristics including the singlet-triplet splitting, degree of entanglement (DOE) and correlation. The mean-field-like single-configuration approaches such as Hartree-Fock and local spin density, lacking correlation, incorrectly identify the ground state symmetry and give inaccurate values for the singlet-triplet splitting and the DOE. The Hubbard model gives qualitatively correct results for the ground state symmetry and singlet-triplet splitting, but produces significant errors in the DOE because it ignores the fact that the strain is asymmetric even if the dots within a molecule are identical. Finally, the Heisenberg model gives qualitatively correct ground state symmetry and singlet-triplet splitting only for rather large inter-dot separations, but it greatly overestimates the DOE as a consequence of ignoring the electron double occupancy effect.

Affiliated with

Also associated with

No associations

Rating

Singlet-triplet splitting, correlation and entanglement of two electrons in quantum dot molecules does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Singlet-triplet splitting, correlation and entanglement of two electrons in quantum dot molecules, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Singlet-triplet splitting, correlation and entanglement of two electrons in quantum dot molecules will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-179971