16.10.Ec Electrons in solids: charge

Absence of spontaneous magnetic order of lattice spins coupled to itinerant interacting electrons in one and two dimensions

Tue, 2012-03-20 11:06 - Lukas Hanschke

Date:

2011-09-01

Author(s):

D. Loss, F.L. Pedrocchi, and A.J. Leggett

Reference:

Phys. Rev. Lett. 107, 107201

URL:

http://prl.aps.org/abstract/PRL/v107/i10/e107201

We extend the Mermin-Wagner theorem to a system of lattice spins which are spin coupled to itinerant and interacting charge carriers. We use the Bogoliubov inequality to rigorously prove that neither (anti-) ferromagnetic nor helical long-range order is possible in one and two dimensions at any finite temperature. Our proof applies to a wide class of models including any form of electron-electron and single-electron interactions that are independent of spin.