Mode Mixing in Antiferromagnetically Correlated Double Quantum Wells

Details Mode Mixing in Antiferromagnetically Correlated Double Quantum Wells Mode Mixing in Antiferromagnetically Correlated Double Quantum Wells

1997-07-30

arxiv.org/abs/cond-mat/9707324v1

Physics

Condensed Matter

Mesoscale and Nanoscale Physics

12 pages, 6 figures, submitted to Phys. Rev. B

Scientific paper

10.1103/PhysRevB.57.2342

We examine the robustness of a recently predicted exchange-induced zero-field magnetic phase in semiconductor double quantum wells in which each well is spin-polarized and the polarization vectors are antiparallel. Magnetic instabilities are a general feature of Coulombic double quantum well systems at low densities. We argue that this antiferromagnetic phase is stabilized relative to ferromagnetic ones by an effective superexchange interaction between the wells. Detailed self-consistent Hartree-Fock calculations using a point-contact model for the interaction show that the antiferromagnetic phase survives intra-subband repulsion matrix elements neglected in earlier work in a large portion of the model's parameter space. We also examine the role of asymmetry due to biasing or to differences in the widths of the two quantum wells. The asymmetry creates a mode coupling between the intra- and inter-subband collective spin-density excitations (SDEs) which changes the Raman spectroscopy signature of the phase transition from a complete softening of the inter-subband SDE to a cusp as the density is tuned through the transition. This cusp may be detectable in inelastic light scattering experiments in samples of sufficient quality at low enough temperatures and densities.

Affiliated with

Also associated with

No associations

Rating

Mode Mixing in Antiferromagnetically Correlated Double Quantum Wells 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 Mode Mixing in Antiferromagnetically Correlated Double Quantum Wells, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mode Mixing in Antiferromagnetically Correlated Double Quantum Wells will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-447196