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Field-induced spin-density wave beyond hidden order in URu₂Si₂.

ABSTRACT: URu₂Si₂ is one of the most enigmatic strongly correlated electron systems and offers a fertile testing ground for new concepts in condensed matter science. In spite of >30 years of intense research, no consensus on the order parameter of its low-temperature hidden-order phase exists. A strong magnetic field transforms the hidden order into magnetically ordered phases, whose order parameter has also been defying experimental observation. Here, thanks to neutron diffraction under pulsed magnetic fields up to 40?T, we identify the field-induced phases of URu₂Si₂ as a spin-density-wave state. The transition to the spin-density wave represents a unique touchstone for understanding the hidden-order phase. An intimate relationship between this magnetic structure, the magnetic fluctuations and the Fermi surface is emphasized, calling for dedicated band-structure calculations.

SUBMITTER: Knafo W

PROVIDER: S-EPMC5080431 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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Field-induced spin-density wave beyond hidden order in URu2Si2.

Knafo W W Duc F F Bourdarot F F Kuwahara K K Nojiri H H Aoki D D Billette J J Frings P P Tonon X X Lelièvre-Berna E E Flouquet J J Regnault L-P LP

Nature communications 20161020

URu2Si2 is one of the most enigmatic strongly correlated electron systems and offers a fertile testing ground for new concepts in condensed matter science. In spite of >30 years of intense research, no consensus on the order parameter of its low-temperature hidden-order phase exists. A strong magnetic field transforms the hidden order into magnetically ordered phases, whose order parameter has also been defying experimental observation. Here, thanks to neutron diffraction u ...[more]

PMID: 27762260

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