String order and symmetries in quantum spin lattices

We show that the existence of string order in a given quantum state is intimately related to the presence of a local symmetry by proving that both concepts are equivalent within the framework of finitely correlated states. Once this connection is established, we provide a complete characterization o...

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Detalhes bibliográficos
Autores: Pérez García, David, Wolf, M.M., Sanz, M., Verstraete, F., Cirac, J.I.
Formato: artículo
Fecha de publicación:2008
País:España
Recursos:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/50312
Acesso em linha:https://hdl.handle.net/20.500.14352/50312
Access Level:acceso abierto
Palavra-chave:530.145
Teoría de los quanta
2210.23 Teoría Cuántica
Descrição
Resumo:We show that the existence of string order in a given quantum state is intimately related to the presence of a local symmetry by proving that both concepts are equivalent within the framework of finitely correlated states. Once this connection is established, we provide a complete characterization of local symmetries in these states. The results allow us to understand in a straightforward way many of the properties of string order parameters, like their robustness or fragility under perturbations and their typical disappearance beyond strictly one-dimensional lattices. We propose and discuss an alternative definition, ideally suited for detecting phase transitions, and generalizations to two and more spatial dimensions.