Fermionic algebraic quantum spin liquid in an octa- kagome frustrated antiferromagnet

Article

关键词: ENTANGLED PAIR STATES;    MATRIX PRODUCT STATES;    MEAN-FIELD THEORY;    RENORMALIZATION-GROUP;    TENSOR NETWORKS;    LATTICE;    DIMENSIONS;    EXCITATIONS;    FORMULATION;    SYSTEMS;   

DOI  :  10.1103/PhysRevB.95.075140

来源: SCIE

【 摘 要 】

We investigate the ground state and finite-temperature properties of the spin-1/2 Heisenberg antiferromagnet on an infinite octa-kagome lattice by utilizing state-of-the-art tensor network-based numerical methods. It is shown that the ground state has a vanishing local magnetization and possesses a 1/2-magnetization plateau with an up-down-up-up spin configuration. A quantum phase transition at the critical coupling ratio J(d)/J(t) = 0.6 is found. When 0 < J(d)/J(t) < 0.6, the system is in a valence bond state, where an obvious zero-magnetization plateau is observed, implying a gapful spin excitation; when J(d)/J(t) > 0.6, the system exhibits a gapless excitation, in which the dimer-dimer correlation is found decaying in a power law, while the spin-spin and chiral-chiral correlation functions decay exponentially. At the isotropic point (J(d)/J(t) = 1), we unveil that at low temperature T, the specific heat depends linearly on T, and the susceptibility tends to a constant for T -> 0, giving rise to a Wilson ratio around unity, implying that the system under interest is a fermionic algebraic quantum spin liquid.

【 授权许可】

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