Flux Period, Spin Gap, and Pairing in the One-Dimensional t-J-J' Model.
Using the factorization of the wave function in the t-J-J' model at small exchange couplings, we demonstrate the connection between the existence of a spin gap and an hc/2e flux periodicity of the ground state energy. We conjecture that all spin-gapped SU(2)-invariant Luttinger liquids have hc/2e flux periodicity, and that this is connected to the fact that a gapped spin-1/2 chain always breaks translational symmetry by doubling the unit cell.
Department of Physics, University of California at Berkeley, Berkeley, California 94720, USA.
Alexander
A
Seidel
Dung-Hai
DH
Lee