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Register a new userAKLT Models with Quantum Spin Glass Ground States
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Added by
Christopher Laumann
Publication date
2010
fields
Physics
and research's language is
English
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We study AKLT models on locally tree-like lattices of fixed connectivity and find that they exhibit a variety of ground states depending upon the spin, coordination and global (graph) topology. We find a) quantum paramagnetic or valence bond solid ground states, b) critical and ordered Neel states on bipartite infinite Cayley trees and c) critical and ordered quantum vector spin glass states on random graphs of fixed connectivity. We argue, in consonance with a previous analysis, that all phases are characterized by gaps to local excitations. The spin glass states we report arise from random long ranged loops which frustrate Neel ordering despite the lack of randomness in the coupling strengths.
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