Quantum phases of a frustrated spin-1 system: The 5/7 skewed ladder

Article

关键词: MATRIX RENORMALIZATION-GROUP;    BOND GROUND-STATES;    HEISENBERG SYSTEMS;    PRODUCT STATES;    DIMERIZATION;   

DOI  :  10.1103/PhysRevB.104.125138

来源: SCIE

【 摘 要 】

The quantum phases in a spin-1 skewed ladder system formed by alternately fusing five- and seven-membered rings are studied numerically using the exact diagonalization technique up to 16 spins and using the density matrix renormalization group method for larger system sizes. The ladder has a fixed isotropic antiferromagnetic (AF) exchange interaction (J(2) = 1) between the nearest-neighbor spins along the legs and a varying isotropic AF exchange interaction (J(1)) along the rungs. As a function of J(1), the system shows many interesting ground states (gs) which vary from different types of nonmagnetic and ferrimagnetic gs. The study of various gs properties such as spin gap, spin-spin correlations, spin density, and bond order reveal that the system has four distinct phases, namely, the AF phase at small J(1); the ferrimagnetic phase with gs spin S-G = n for 1.44 < J(1) < 4.74 and with S-G = 2n for J(1) > 5.63, where n is the number of unit cells; and a reentrant nonmagnetic phase at 4.74 < J(1) < 5.44. The system also shows the presence of spin current at specific J(1) values due to simultaneous breaking of both reflection and spin parity symmetries.

【 授权许可】

Free