Impurity-Bond Effect on the Spin-1 Antiferromagnetic Heisenberg Chain

Abstract

Low-lying excited states of the spin-1 antiferromagnetic Heisenberg chain with an impurity bond are investigated in terms of domain-wall excitations by means of analytical methods as well as a method of numerical diagonalization. It is shown that 1) the impurity bond brings about a massive triplet mode in the Haldane gap, 2) the triplet state comprises three of the four ground states of an open chain, 3) the excited states with the domain wall trapped at the impurity bond, including the massive triplet mode, exhibit a Néel-type configuration of the magnetic moment around the impurity bond. On the basis of the present results, we propose a new energy versus magnetic-field diagram.

11 pages + 5 figures available upon request from [email protected], TeX, KOBE-CCS-93-01

References in corpus (1)

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

Cited by in corpus (11)

• Impurities in $s=1$ Heisenberg Antiferromagnets
• Variational Matrix Product Ansatz for Nonuniform Dynamics in the Thermodynamic Limit
• Propagating S=1/2 particles in S=1 Haldane gap systems
• Excitation Spectrum of the Spin-1/2 Ferromagnetic-Antiferromagnetic Alternating Heisenberg Chain:
• Effect of a Spin-1/2 Impurity on the Spin-1 Antiferromagnetic Heisenberg Chain
• Impurity Energy Level Within The Haldane Gap
• Spin-1 chain doped with mobile S=1/2 fermions
• Doped two orbital chains with strong Hund's rule couplings - ferromagnetism, spin gap, singlet and triplet pairings
• Temperature dependence of local states due to S=1/2 impurities and their correlation in a S=1 Heisenberg chain
• Numerical Study of the Spin-1 Antiferromagnetic Heisenberg Chain with a Spin-1/2 Impurity
• Energy Versus Magnetic-Field Diagram of the Spin-1 Haldane System with an Impurity