Spin-droplets in confined quantum Hall systems
Abstract
Two-dimensional semiconductor quantum dots are studied in the the filling-factor range 2<v<3. We find both theoretical and experimental evidence of a collective many-body phenomenon, where a fraction of the trapped electrons form an incompressible spin-droplet on the highest occupied Landau level. The phenomenon occurs only when the number of electrons in the quantum dot is larger than ~30. We find the onset of the spin-droplet regime at v=5/2. This proposes a finite-geometry alternative to the Moore-Read-type Pfaffian state of the bulk two-dimensional electron gas. Hence, the spin-droplet formation may be related to the observed fragility of the v=5/2 quantum Hall state in narrow quantum point contacts.
Cite
@article{arxiv.0712.0991,
title = {Spin-droplets in confined quantum Hall systems},
author = {E. Rasanen and H. Saarikoski and A. Harju and M. Ciorga and A. S. Sachrajda},
journal= {arXiv preprint arXiv:0712.0991},
year = {2008}
}
Comments
To appear in Phys. Rev. B (Rapid. Comm.)