2011/03/31 by J. C. Xavier, F. C. Alcaraz, F C Alcaraz · 1 citation
Physics and Astronomy · #Anisotropy #Condensed matter physics #Entropy (arrow of time) #Mathematical physics #Model Reduction and Neural Networks #Physics #Quantum and electron transport phenomena #Quantum many-body systems #Quantum mechanics #Renormalization group #cond-mat.stat-mech #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.83.214425
published as Phys. Rev. B 83, 214425 (2011) · revised version, accepted to PRB. 9 pages, 3 Figures, 4 Tables
arxiv created 2011/06/03 · openalex publication_date 2011/06/29 · arxiv updated 2015/05/27 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Using the density matrix renormalization group, we investigate the R'enyi entropy of the anisotropic spin-s Heisenberg chains in a z-magnetic field. We considered the half-odd-integer spin-s chains, with s=1/2, 3/2, and 5/2, and periodic and open boundary conditions. In the case of the spin-1/2 chain we were able to obtain accurate estimates of the new parity exponents p_\ensuremathα(p) and p_\ensuremathα(o) that gives the power-law decay of the oscillations of the \ensuremathα-R'enyi entropy for periodic and open boundary conditions, respectively. We confirm the relations of these exponents with the Luttinger parameter K, as proposed by Calabrese et al. [Phys. Rev. Lett. 104, 095701 (2010)]. Moreover, the predicted periodicity of the oscillating term was also observed for some nonzero values of the magnetization m. We show that for s>1/2 the amplitudes of the oscillations are quite small and get accurate estimates of p_\ensuremathα(p) and p_\ensuremathα(o) become a challenge. Although our estimates of the new universal exponents p_\ensuremathα(p) and p_\ensuremathα(o) for the spin-3/2 chain are not so accurate, they are consistent with the theoretical predictions.