Physical Review B
We investigate the application of a perturbative renormalization group (RG) method to random antiferromagnetic Heisenberg chains with arbitrary spin size. At zero temperature we observe that initial arbitrary probability distributions develop a singularity at J = 0, for all values of spin S. When the RG method is extended to finite temperatures, without any additional assumptions, we find anomalous results for S >= 1. These results lead us to conclude that the perturbative scheme is not adequate to study random chains with S >= 1. Therefore a random singlet phase in its more restrictive definition is only assured for spin-1/2 chains.
Energy levels (Quantum mechanics); Quantum theory
Citation: Pilot Scholars Version (Modified MLA Style)
Saguia, A.; Boechat, B.; Continentino, M. A.; and Bonfim, O. F. de Alcantara, "Breakdown of the perturbative renormalization group for S >= 1 random antiferromagnetic spin chains" (2001). Physics Faculty Publications and Presentations. Paper 12.