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Restoration of the third law in spin ice thin films.

ABSTRACT: A characteristic feature of spin ice is its apparent violation of the third law of thermodynamics. This leads to a number of interesting properties including the emergence of an effective vacuum for magnetic monopoles and their currents - magnetricity. Here we add a new dimension to the experimental study of spin ice by fabricating thin epitaxial films of Dy2Ti2O7, varying between 5 and 60 monolayers on an inert substrate. The films show the distinctive characteristics of spin ice at temperatures >2?K, but at lower temperature we find evidence of a zero entropy state. This restoration of the third law in spin ice thin films is consistent with a predicted strain-induced ordering of a very unusual type, previously discussed for analogous electrical systems. Our results show how the physics of frustrated pyrochlore magnets such as spin ice may be significantly modified in thin-film samples.

SUBMITTER: Bovo L

PROVIDER: S-EPMC3959195 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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Restoration of the third law in spin ice thin films.

Bovo L L Moya X X Prabhakaran D D Soh Yeong-Ah YA Boothroyd A T AT Mathur N D ND Aeppli G G Bramwell S T ST

Nature communications 20140312

A characteristic feature of spin ice is its apparent violation of the third law of thermodynamics. This leads to a number of interesting properties including the emergence of an effective vacuum for magnetic monopoles and their currents - magnetricity. Here we add a new dimension to the experimental study of spin ice by fabricating thin epitaxial films of Dy2Ti2O7, varying between 5 and 60 monolayers on an inert substrate. The films show the distinctive characteristics of spin ice at temperature ...[more]

PMID: 24619137

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