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arXiv · 2101.07300

Quantum fluctuation effects on the ordered Moments in a two dimensional frustrated ferrimagnet

Kingshuk Majumdar·Subhendra D. Mahanti
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Abstract

We propose a novel two-dimensional (2D)frustrated quantum spin-1/2 anisotropic Heisenberg model with alternating ferromagnetic and antiferromagnetic magnetic chains along one direction and antiferromagnetic interactions along the other. The (mean-field) ground state is ferrimagnetic in certain range of the interaction space. Spin-wave theory analysis of the reduction of ordered moments at inequivalent spin sites and the instability of the spin waves suggest a quantum phase transition which has the characteristics of both the frustrated two-dimensional antiferromagnetic S=1/2 ($J_1, J_2$) model and 1D S$_1$=1, S$_2$=1/2 quantum ferrimagnetic model.

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Kingshuk Majumdar, Subhendra D. Mahanti. 2021-01-18. Quantum fluctuation effects on the ordered Moments in a two dimensional frustrated ferrimagnet. https://doi.org/10.1088/1361-648x/abd8b6

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