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Local quantum phase transition in YFe2Al10.

ABSTRACT: A phase transition occurs when correlated regions of a new phase grow to span the system and the fluctuations within the correlated regions become long lived. Here, we present neutron scattering measurements showing that this conventional picture must be replaced in YFe2Al10, a compound that forms naturally very close to a [Formula: see text] quantum phase transition. Fully quantum mechanical fluctuations of localized moments are found to diverge at low energies and temperatures; however, the fluctuating moments are entirely without spatial correlations. Zero temperature order in YFe2Al10 is achieved by an entirely local type of quantum phase transition that may originate with the creation of the moments themselves.

SUBMITTER: Gannon WJ

PROVIDER: S-EPMC6142233 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Local quantum phase transition in YFe2Al10.

Gannon W J WJ Wu L S LS Zaliznyak I A IA Xu W H WH Tsvelik A M AM Qiu Y Y Rodriguez-Rivera J A JA Aronson M C MC

Proceedings of the National Academy of Sciences of the United States of America 20180618 27

A phase transition occurs when correlated regions of a new phase grow to span the system and the fluctuations within the correlated regions become long lived. Here, we present neutron scattering measurements showing that this conventional picture must be replaced in YFe2Al10, a compound that forms naturally very close to a [Formula: see text] quantum phase transition. Fully quantum mechanical fluctuations of localized moments are found to diverge at low energies and tempera ...[more]

PMID: 29915042

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