The phase diagram of the extended anisotropic ferromagnetic-antiferromagnetic Heisenberg chain
Dipartimento di Fisica “E.R. Caianiello”, Università degli Studi di Salerno, 84084 Fisciano (SA), Italy
2 Unità CNISM di Salerno, Università degli Studi di Salerno, 84084 Fisciano (SA), Italy
3 CNR-SPIN, UoS di Salerno, 84084 Fisciano (SA), Italy
Revised: 14 August 2010
Published online: 22 September 2010
By using Density Matrix Renormalization Group (DMRG) technique we study the phase diagram of 1D extended anisotropic Heisenberg model with ferromagnetic nearest-neighbor and antiferromagnetic next-nearest-neighbor interactions. We analyze the static correlation functions for the spin operators both in- and out-of-plane and classify the zero-temperature phases by the range of their correlations. On clusters of 64, 100, 200, 300 sites with open boundary conditions we isolate the boundary effects and make finite-size scaling of our results. Apart from the ferromagnetic phase, we identify two gapless spin-fluid phases and two ones with massive excitations. Based on our phase diagram and on estimates for the coupling constants known from literature, we classify the ground states of several edge-sharing materials.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2010