Logarithmic corrections to the ground-state energy of finite spin−12 antiferromagnetic chains due to ferromagnetic end bonds
Jizhong Lou, Jianhui Dai, Shaojin Qin +2 more
We analyze the logarithmic corrections due to ferromagnetic impurity ending bonds of open spin-1/2 antiferromagnetic chains, using the density matrix renormalization group technique. A universal finite-size scaling $\ensuremath{\sim}1/(L\mathrm{ln}L)$ for impurity contributions in the quasidegenerate ground-state energy is demonstrated for a zigzag spin-1/2 chain at the critical next-nearest-neighbor coupling and the standard Heisenberg spin-1/2 chain, in the long-chain limit. Using an exact solution for the latter case it is argued that one can extract the impurity contributions to the entropy and specific heat from the scaling analysis. It is also shown that a pure spin-3/2 open Heisenberg chain belongs to the same universality class.
arXiv:cond-mat/0003071•Physical review. B, Condensed matter•Oct 1, 2000•12 citations