Effect of Spin-1/2 Impurity on Spin-1 Antiferromagnetic Heisenberg Chain

Evidence for the Singlet-Dimer Ground State in anS=1Antiferromagnetic Bond Alternating Chain

“…The phenomenological Hamiltonian like Eq. (2) for the edge spin in Cu-doped NENP is derived from a more realistic Hamiltonian including the bulk chain part [13]. The anisotropic exchange interaction in the phenomenological Hamiltonian was explained by this analysis.…”

“…The anisotropic exchange interaction in the phenomenological Hamiltonian was explained by this analysis. On applying this method [13] to our case, the effective D 0 value, which is different from that of the bulk chain, must be derived. But, this derivation is beyond the scope of our experimental paper.…”

Numerical Study of the Spin-1 Antiferromagnetic Heisenberg Chain with a Spin-1/2 Impurity

“…The coefficients a (M,P ) and b (M,P ) thus determined numerically are presented in Table III. As is shown in the Appendix, our analytical study 17) has led to the results, a are listed in Table III. As we will discuss in §3, …”

“…As can be seen from the analytical result obtained in ref. 17, these states are those with the lowest three energy eigenvalues within the M = 1/2 subspace and that with the lowest energy eigenvalue within the M = 3/2 subspace. In the following the four eigenvalues for a given value of N are represented by ǫ (M,P ) (N ), where the different states are denoted by (M, P ) with P (= +, −) which stands for the parity with respect to reflection around the impurity spin; we have two different (1/2, +) states and the prime is added to the state with the larger eigenvalue to distinguish between these two states.…”

Characterization of localized effective spins in gapped quantum spin chains

“…For example, edges and impurities of the S = 1 antiferromagnetic Heisenberg chain have been studied extensively [7][8][9][10][11]. Moreover, localized spin moments at the inhomogeneous structure are pointed out in several systems [12,13].…”