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arXiv · 0909.2182

Spin models of quasi-1D quantum ferrimagnets with competing interactions

N. B. Ivanov
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Abstract

We present a brief survey of the recent theoretical work related to generic Heisenberg spin models describing quasi-one-dimensional quantum ferrimagnets. The emphasis is on quantum chains and ladders with strong competing interactions, such as the frustrated $J_1-J_2$ chain with alternating (1,1/2) spins, the spin-1/2 diamond chain with four-spin cyclic couplings, and some generic types of mixed-spin ladders with geometric frustration. As a rule, discussed models exhibit rich quantum phase diagrams and provide some interesting examples of one-dimensional magnetic-paramagnetic quantum phase transitions. A number of open problems in the reviewed research area are discussed.

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N. B. Ivanov. 2009-09-11. Spin models of quasi-1D quantum ferrimagnets with competing interactions. https://arxiv.org/abs/0909.2182

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