Density matrix renormalization group study of critical behavior of the spin-(1)/(2) alternating Heisenberg chain

作者：Papenbrock T^*; Barnes T; Dean DJ; Stoitsov MV; Strayer MR

来源：Physical Review B, 2003, 68(2): 024416.

DOI：10.1103/PhysRevB.68.024416

We investigate the critical behavior of the S = 1/2 alternating Heisenberg chain using the density matrix renormalization group. The ground-state energy per spin, (e) over tilde (o), and singlet-triplet energy gap (Delta) over tilde are determined for a range of alternations delta. Our results for the approach of (e) over tilde (o) to the uniform chain limit are well described by c(deltap), with p approximate to 1.45. The singlet-triplet gap is also well described by a power law, with p approximate to 0.73, half of the eo power. The renormalization group predictions of power laws with logarithmic corrections can also accurately describe our data provided that a surprisingly large-scale parameter delta(o) is present in the logarithms.

• 出版日期2003-7-1