Numerical Studies of Antiferromagnetic Spin Chains(反強磁性鎖の数値的研究)

KIYOMI OKAMOTO

Djalma Medeiros, G. G. Cabrera

Shoji Yamamoto

Magnetic susceptibilities of spin-$(S,s)$ ferrimagnetic Heisenberg chains are numerically investigated. It is argued how the ferromagnetic and antiferromagnetic features of quantum ferrimagnets are exhibited as functions of $(S,s).$ Spin-$(S,s)$ ferrimagnetic chains behave similar to combinations of spin-$(S\ensuremath{-}s)$ ferromagnetic and spin-$(2s)$ antiferromagnetic chains provided $S=2s.$

P. J. Freitas

M. Shahri Naseri, R. Kamran, S. Mahdavifar

We presented a numerical study of the magnetization process of frustrated spin-1/2 chain. Using the exact diagonalization technique, we provided the evidence that a plateau at one-third of the saturation magnetization exists in the magnetization curve of frustrated antiferromagnetic spin-1/2 chain.

Victor Barzykin, Ian K. Affleck

Corrections to the asymptotic correlation function in a Heisenberg spin- antiferromagnetic spin chain are known to vanish slowly (logarithmically) as a function of the distance r or the chain size L . This leads to significant differences with numerical results. We calculate the sub-leading logarithmic corrections to the finite-size correlation function, using renormalization group improved perturbation theory, and compare the result with numerical data.