Le Journal de Physique Colloques
GROUND-STATE PROPERTIES OF THE ONE-DIMENSIONAL SPIN-1/2 HEISENBERG-XY ANTIFERROMAGNET WITH COMPETING INTERACTIONS
Takashi Tonegawa, I. Harada
Abstract
We study the ground-state properties of the one-dimensional spin-1/2 Heisenberg-XY magnet with antiferromagnetic first- and second-neighbor interactions. Extrapolating exact results for finite-size systems of up to 20 spins, we estimate the behavior at the infinite-size limit. The limiting ground state has a finite gap when the second-neighbor interaction is sufficiently large.