Local quantum phase transition in YFe2Al10

W. J. Gannon, L. S. Wu, I. A. Zaliznyak, W. H. Xu, A. M. Tsvelik, Y. Qiu, J. A. Rodriguez-Rivera, and M. C. Aronson
PNAS July 3, 2018 115 (27) 6995-6999; published ahead of print June 18, 2018 https://doi.org/10.1073/pnas.1721493115

  1. Edited by Subir Sachdev, Harvard University, Cambridge, MA, and approved May 9, 2018 (received for review December 13, 2017)

Significance

We report the discovery of a type of phase transition that occurs at T=0. In continuous phase transitions, order occurs when the size and lifetime of small ordered regions increase until they span the system and become static. Reported here is experimental evidence of a transition where this paradigm fails. Our observed phase transition is local, where each magnetic moment in YFe2Al10 is independent of every other moment, yet each moment follows the same spectrum of quantum critical fluctuations. The phase transition present in YFe2Al10 is a realization of a scenario only hinted at by theory, corresponding to the formation of magnetic moments, with no evidence for the breaking of translational symmetry that accompanies magnetic order.

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 T=0 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.

Footnotes

  • ↵1To whom correspondence should be addressed. Email: wgannon{at}physics.tamu.edu.

  • ↵2Department of Physics, South University of Science and Technology of China, Shenzhen, 518055, China.

  • Author contributions: W.J.G., L.S.W., and M.C.A. designed research; W.J.G., L.S.W., I.A.Z., W.H.X., A.M.T., Y.Q., J.A.R.-R., and M.C.A. performed research; W.J.G. analyzed data; and W.J.G., L.S.W., I.A.Z., W.H.X., A.M.T., Y.Q., J.A.R.-R., and M.C.A. wrote the paper.

  • The authors declare no conflict of interest.

  • This article is a PNAS Direct Submission.

  • This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1721493115/-/DCSupplemental.

Published under the PNAS license.

View Full Text
Back to top
Article Alerts
Email Article
Citation Tools
Request Permissions
Local quantum phase transition in YFe2Al10
W. J. Gannon, L. S. Wu, I. A. Zaliznyak, W. H. Xu, A. M. Tsvelik, Y. Qiu, J. A. Rodriguez-Rivera, M. C. Aronson
Proceedings of the National Academy of Sciences Jul 2018, 115 (27) 6995-6999; DOI: 10.1073/pnas.1721493115
del.icio.us logo Digg logo Reddit logo Twitter logo CiteULike logo Facebook logo Google logo Mendeley logo
Proceedings of the National Academy of Sciences: 116 (8)
Current Issue

Submit

Jump to section

You May Also be Interested in

Nonmonogamous strawberry poison frog (Oophaga pumilio). Image courtesy of Yusan Yang (University of Pittsburgh, Pittsburgh).
Putative signature of monogamy
A study suggests a putative gene-expression hallmark common to monogamous male vertebrates of some species, namely cichlid fishes, dendrobatid frogs, passeroid songbirds, common voles, and deer mice, and identifies 24 candidate genes potentially associated with monogamy.
Image courtesy of Yusan Yang (University of Pittsburgh, Pittsburgh).
Active lifestyles. Image courtesy of Pixabay/MabelAmber.
Meaningful life tied to healthy aging
Physical and social well-being in old age are linked to self-assessments of life worth, and a spectrum of behavioral, economic, health, and social variables may influence whether aging individuals believe they are leading meaningful lives.
Image courtesy of Pixabay/MabelAmber.