Charge and spin reconstruction in quantum Hall strips

Abstract

We study the effect of electron-electron interactions on the charge and spin structures of a quantum Hall strip in a triangularly confined potential. We find that the strip undergoes a spin-unpolarized to spin-polarized transition as a function of magnetic field perpendicular to the strip. For sharp confinements, the spin-polarization transition is spontaneous and first develops at the softer side of the triangular potential, which shows up as an ``eye structure'' in the electron dispersion. For sufficiently weak confinements, this spin-polarization transition is preceded by a charge reconstruction of a single spin species, which creates a spin-polarized strip of electrons with a width of the order of the magnetic length detached from the rest of the system. The relevance of our findings to the recent momentum-resolved tunneling experiments is also discussed.