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arXiv · 0812.0133

Diamond chains with multiple-spin exchange interactions

N. B. Ivanov·J. Richter·J. Schulenburg
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Abstract

We study the phase diagram of a symmetric spin-1/2 Heisenberg diamond chain with additional cyclic four-spin exchange interactions. The presented analysis supplemented by numerical exact-diagonalization results for finite periodic clusters implies a rich phase diagram containing, apart from standard magnetic and spin-liquid phases, two different tetramer-dimer phases as well as an exotic four-fold degenerate dimerized phase. The characteristics of the established spin phases as well as the nature of quantum phase transitions are discussed, as well.

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N. B. Ivanov, J. Richter, J. Schulenburg. 2009-03-17. Diamond chains with multiple-spin exchange interactions. https://doi.org/10.1103/physrevb.79.104412

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